1 2 3 4 5 - Just T4'sjust-t4s.co.uk/downloads/fuel_exhaust.pdf · Pierburg/Solex 31 PIC-7 ... Carburettor (1.05 litre engine) - adjustments . . . . . . . . . . . . . . . . . . . 15

1081 VW Golf & Jetta

4A

Chapter 4 Part A:Fuel and exhaust systems - carburettor models

Air cleanerType . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Automatic air temperature controlElement type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Renewable paperElement application:

1.05 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion Wl011.3 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion W1021.6 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion U5081.8 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion U508

Fuel pumpType:

1.05 and 1.3 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mechanical, diaphragm, operated by plunger from camshaft1.6 and 1.8 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mechanical, diaphragm, operated by eccentric on intermediate shaft

Fuel filterType . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion L104

Carburettor - 1.05 litrePierburg/Solex 31 PIC-7Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Downdraught with manual or automatic choke Venturi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 mmMain jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . X117.5 Air correction jet with emulsion tube . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 ZIdling fuel jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Idling air jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135Auxiliary fuel jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32.5Auxiliary air jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130Enrichment (primary/secondary) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70/70 Injection capacity (cc/stroke) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.00 ± 0.15Float needle valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5 Float needle valve washer thickness . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 mmFast idle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2600 ± 100 rpmChoke valve gap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.8 ± 0.2 mmThrottle valve gap smooth running detent . . . . . . . . . . . . . . . . . . . . . . . 2.5 ± 0.3 mmIdle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 950 ± 50 rpmCO content % . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 ± 0.5

Accelerator and throttle cables - removal, refitting and adjustment . 10Accelerator pedal - removal and refitting . . . . . . . . . . . . . . . . . . . . . 11Air cleaner element - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Air cleaner unit - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . 3Automatic air cleaner temperature control - testing . . . . . . . . . . . . . 4Carburettor (1.05 litre engine) - adjustments . . . . . . . . . . . . . . . . . . . 15Carburettor (1.3 litre engine) - adjustments . . . . . . . . . . . . . . . . . . . . 16Carburettor (1.6 & 1.8 litre engines) - adjustments . . . . . . . . . . . . . . 17Carburettor - overhaul . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Carburettor - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Choke cable (1.05 litre engine) - removal, refitting and adjustment . 12Exhaust system - inspection, removal and refitting . . . . . . . . . . . . . 20Fuel filler gravity valve - removal, testing and refitting . . . . . . . . . . .. 9Fuel gauge sender unit - removal and refitting . . . . . . . . . . . . . . . . . 8Fuel pump - testing, removal and refitting . . . . . . . . . . . . . . . . . . . . . 5Fuel reservoir - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . 6Fuel tank - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7General information and precautions . . . . . . . . . . . . . . . . . . . . . . . . 1Inlet and exhaust manifolds - removal and refitting . . . . . . . . . . . . . 19Inlet manifold preheating - testing . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

4A•1

Specifications

Contents

Easy, suitable fornovice with littleexperience

Fairly easy, suitablefor beginner withsome experience

Fairly difficult,suitable for competentDIY mechanic

Difficult, suitable forexperienced DIYmechanic

Very difficult,suitable for expert DIYor professional

Degrees of difficulty

54321

Carburettor - 1.05 litre (continued)

Pierburg/Solex 1B3Venturi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 mmMain jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105Air correction jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57.5Idling fuel/air jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50/130Pump injection tube . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32.5/150Needle valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5Accelerator pump capacity (cc/stroke) . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 ± 0.15Choke valve gap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.8 ± 0.2 mmFast idle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2000 ± 100 rpmIdle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 800 ± 50 rpmCO content % . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 ± 0.5

Weber 32 TLAVenturi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 mmMain jet:

Code 030 129 016 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105Code 030 129 016 D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

Air correction jet:Code 030 129 016 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80Code 030 129 016 D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

Emulsion tube . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F96Idling fuel jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47Idling air jet:

Code 030 129 016 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110Code 030 129 016D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

Auxiliary fuel jet (code 030 129 016D) . . . . . . . . . . . . . . . . . . . . . . . . . . 30Auxiliary air jet (code 030 129 016D) . . . . . . . . . . . . . . . . . . . . . . . . . . . 170Pump injection tube . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.35/0.35Needle valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.75Needle valve washer thickness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.75 mmAccelerator pump capacity (cc/stroke) . . . . . . . . . . . . . . . . . . . . . . . . . . 1.05 ± 0.15Choke valve gap (pull-down):

Without vacuum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 ± 0.2 mmWith 300 mbar vacuum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 ± 0.2 mm

Choke valve gap (wide open kick):Code 030 129 016 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 ± 0.5 mmCode 030 129 01 6D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 ± 0.5 mm

Float level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28.0 ± 1.0 mmFast idle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2000 ± 100 rpmIdle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 800 ± 50 rpmCO content % . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 ± 0.5

Carburettor - 1.3 litre

Pierburg/Solex 2E3Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Twin progressive choke, downdraught with automatic choke

Stage I Stage IIVenturi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 23Main jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . X95 X110Air correction jet with emulsion tube . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 130Idling fuel/air jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45/130 -Full throttle enrichment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 95Pump injection tube diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.35 mm -Choke cover code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276Injection capacity (cc/stroke) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 ± 0.15Locking lever clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.4 ± 0.15 mmFull throttle enrichment - height above atomiser . . . . . . . . . . . . . . . . . . 12.0 mmChoke valve gap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 ± 0.1 mmFast idle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2000 ± 100 rpmIdle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 800 ± 50 rpmC0 content % . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 ± 0.5

4A•2 Fuel and exhaust systems - carburettor models


Carburettor-1.6 litre

Pierburg/Solex 2E2 - engine code EZType . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Twin progressive choke, downdraught with automatic choke

Stage I Stage IIVenturi diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22.0 mm 26.0 mmMain jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . X110 X127Air correction jet with emulsion tube . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.75/1.05 mm 1.05 mmIdle fuel/air jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42.5 -Full throttle enrichment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 0.7Pump injection tube . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5 -Injection capacity (cc/stroke) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 ± 0.15Choke valve gap with primary throttle open 45° . . . . . . . . . . . . . . . . . . 6.3 ± 0.3 mmFast idle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3000 ± 200 rpmIdle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 950 ± 50 rpmIncreased idle speed:

Automatic transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 800 rpmAir conditioner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 950 ± 50 rpm

CO content % . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 ± 0.5

Pierburg/Solex 2E2 - engine code RF Stage I Stage IIVenturi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22.0 mm 26.0 mmMain jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102.5 127.5Air correction jet with emulsion tube. . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 105Idle fuel/air jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42.5 -Fuel throttle enrichment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 0.7Accelerator pump injection tube . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5 -Choke valve gap:

Manual gearbox . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 ± 0.15 mm 5.0 ± 0.15 mmAutomatic transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.9 ± 0.15 mm 5.3 ± 0.15 mm

Accelerator pump capacity (cc/stroke) . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 ± 0.15Fast idle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3000 ± 200 rpmIdle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 750 ± 50 rpmCO content % . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 to 1.5

Carburettor - 1.8 litre

Pierburg/Solex 2E2Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Twin progressive choke, downdraught with automatic choke

Stage I Stage IIVenturi diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22.0 mm 26.0 mmMain jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . X105 X120Air correction jet with emulsion tube . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 mm 100 mmIdle fuel/air jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42.5 -Full throttle enrichment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 0.9Pump injection tube:

Carburettor part number type 027 129 015 . . . . . . . . . . . . . . . . . . . . 0.35 -Carburettor part number type 027 129 015 Q . . . . . . . . . . . . . . . . . . 0.5 -

Injection capacity (cc/stroke) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 ± 0.15Choke valve gap (measured at lower edge) . . . . . . . . . . . . . . . . . . . . . . 2.3 ± 0.15 mm 4.7 ± 0.15 mmFast idle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3000 ± 200 rpmIdle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 950 ± 50 rpmIncreased idle speed:

Automatic transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 800 rpmAir conditioner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 950 ± 50 rpm

CO content % . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 ± 0.5

Torque wrench settings Nm lbf ft

1.05 and 1.3 litreCarburettor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 7Intermediate flange . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 7Inlet manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18Inlet manifold preheater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 7Fuel tank strap bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18Exhaust manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18Exhaust manifold to downpipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18Exhaust pipe clamp bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18

Fuel and exhaust systems - carburettor models 4A•3

4A


Torque wrench settings (continued) Nm lbf ft

1.6 and 1.8 litreCarburettor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5Fuel pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 15Inlet manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18Inlet manifold preheater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 7Fuel tank strap bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18Exhaust manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18Exhaust pipe clip:

8 mm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 1810 mm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 30

1 General information andprecautions

General informationThe fuel system comprises a rear-mounted

fuel tank, a mechanical diaphragm fuel pumpand a downdraught carburettor.

The pump on 1.05 and 1.3 litre models isoperated by means of a plunger activated bythe camshaft, whilst on 1.6 and 1.8 litremodels, it is operated directly by an eccentricon the intermediate shaft.

The air cleaner unit contains a renewablepaper element and incorporates an automatictemperature control.

A conventional exhaust system is used onall models, being fitted in sections for ease ofreplacement.

Precautions

Fuel warningMany of the procedures in thisChapter require the removal offuel lines and connections whichmay result in some fuel spillage.

Before carrying out any operation on thefuel system refer to the precautions givenin Safety first! at the beginning of thisManual and follow them implicitly. Petrol isa highly dangerous and volatile liquid andthe precautions necessary when handlingit cannot be overstressed.

Tamperproof adjustment screwsCertain adjustment points in the fuel system

are protected by “tamperproof” caps, plugs orseals. The purpose of such tamperproofing is

to discourage, and to detect, adjustment byunqualified operators.

In some EEC countries (though not in theUK), it is an offence to drive a vehicle withmissing or broken tamperproof seals. Beforedisturbing a seal, satisfy yourself that you willnot be breaking any anti-pollution regulationsby doing so. Fit a new seal when adjustmentis complete, if this is required by law.

Do not break tamperproof seals on avehicle which is still under warranty.

Unleaded petrol - usageFor full information on the use of unleaded

petrol, consult your VW dealer who will beable to inform you if your vehicle is capable ofrunning on unleaded fuel and, where possible,of the necessary adjustments required. Theuse of unleaded fuel in a vehicle not designed,or suitably adjusted, to run on unleaded fuelwill lead to serious damage of the valve seats.

2 Air cleaner element - renewal 1Refer to Chapter 1, Section 32

3 Air cleaner unit - removal andrefitting 2

1.05 and 1.3 litre engines1 Remove the element. 2 Unscrew the nut(s) securing the air cleanerbody and remove the adapter or retaining ring(see illustration).

3 Note the location of all hoses and tubesthen disconnect them. Withdraw the aircleaner body from the carburettor and removethe sealing ring (see illustrations). 4 Refit in the reverse order of removal,ensuring that all hose connections aresecurely made.

1.6 and 1.8 litre engines5 Remove the element.6 Unclip and detach the air hose at the sideof the cleaner body (see illustration).7 Undo the retaining nut at the top and lift thecleaner unit clear, disconnecting theremaining hoses.8 Refit in the reverse order of removal. Fit anew sealing washer if the old one hasperished or distorted.

4 Automatic air cleanertemperature control - testing 2

1 Unclip and remove the vacuum unit andinlet pipe but leave the vacuum pipeconnected (see illustration).2 Suspend a thermometer in the flow of airthrough the inlet duct then start the engine.Between -20°C and + 20°C, the control flap inthe unit should be a maximum of 2/3rds opento admit hot air from the exhaust manifold.Above 20°C, the control flap must close thehot air supply (see illustration).3 The control flap movement can be checkedby sucking on the vacuum inlet.4 With the engine running and inlet airtemperature above 20°C, disconnect thevacuum hose from the vacuum unit. Thecontrol flap should fully open within amaximum of 20 seconds.


3.2 Removing air cleaner body retainingring - 1.3 litre

3.3a Disconnecting temperature sensorhose . . .

3.3b . . . and crankcase emission hose -1.3 litre



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3.6 Air cleaner components – 1.6 and 1.8 litre

1 Warm air deflector plate2 Gasket3 Spring washer4 Nut5 Air hose6 Bracket7 Washer8 Nut9 Bonded rubber mounting10 Clip11 Air Hose12 Clip13 Spacer tube14 Air cleaner15 Clip16 Stud17 Washer18 Self-locking nut19 Filter element20 Sealing washer21 Spring22 Lockplate23 Retaining clip24 Dual thermostat25 Union26 Air hose27 Clip

4.2 Air cleaner load and temperature control diagram – 1.05 and 1.3 litre

A Temperature regulatorB Intake pipe with thermostat

C Vacuum unit4.1 Air cleaner vacuum unit

5 If the control unit does not operate correctlythen renew it, together with the temperaturesensor (see illustration).6 Refit the vacuum unit and inlet pipe.

5 Fuel pump - testing, removaland refitting 3

Testing1 Pump location is dependent on engine typeand is as follows:a) 1.05 and 1.3 litre engines - The pump is

located on the right-hand side of theengine, forward of the carburettor (seeillustration). Mounted on the cylinderhead, it is driven indirectly from thecamshaft.

b) 1.6 and 1.8 litre engines - The pump islocated on the side of the cylinder block,next to the oil filter mounting bracket. It isdriven direct from the intermediate shaft.

2 If the pump is suspected of malfunctioning,disconnect the supply pipe from thecarburettor (air cleaner removed) and the LTlead from the coil positive terminal. Ensurethat there is fuel in the tank. Turn the engineon the starter while holding a wad of rag nearthe fuel pipe. If the pump is operatingcorrectly, well defined spurts of fuel should beejected from the pipe.3 If the pump is malfunctioning then it mustbe renewed, as it is not possible to service orrepair it. However, prior to removal of thepump, check the in-line filter for blockage.

Removal4 To remove the fuel pump, first identify thehoses for position then disconnect them fromthe pump (see illustrations).5 Using a suitable splined or Allen key,unscrew the pump retaining bolts andwithdraw the unit from the cylinder head orcylinder block (as applicable). Remove thesealing ring and, if applicable, note the earthlead location.

6 Clean the mating faces of the pump andcylinder head or cylinder block/seal flange.

Refitting7 Refitting is a reversal of the removalprocedure. Renew the seal ring and, wherecrimped type hose clips were used, changethem to screw type clips.8 On completion, check all hose connectionswith the engine running and look for any signof fuel leakage.


4.5 Upper view of air temperature sensor -1.3 litre

5.1 Fuel pump location - 1.3 litre


5.4a Fuel line attachments – 1.05 and 1.3 litre

5.4b Fuel pump and line connections – 1.6 and 1.8 litre

6 Fuel reservoir - removal andrefitting 2

1 The fuel reservoir is located between thefuel pump and the carburettor (seeillustration). The reservoir has three hoseconnections which are marked as follows:a) From the pump - arrow markedb) To the carburettor - not markedc) To the fuel return line - marked R

2 To remove the reservoir, disconnect thethree hoses and plug them to prevent leakage.3 Remove the support bracket retainingscrews and lift away the reservoir. Note theearth lead connection (see illustration).4 Refit in the reverse order to removal andthen check for any signs of leakage oncompletion.

7 Fuel tank - removal andrefitting 3

Warning: The fuel tank mustalways be removed in a wellventilated area and never over apit

Removal1 Disconnect the battery negative lead.2 Siphon or pump all the fuel from the tank(there is no drain plug) .

3 Lift the floor covering from the luggagecompartment then remove the circular senderunit cover (see illustration).4 Disconnect the wiring plug from the top ofthe sender unit, also the fuel feed (to pump)and return (from fuel reservoir) hoses.5 Jack up the rear of the vehicle and supportit on axle stands (see “Jacking and vehiclesupport”). Chock the front wheels, remove theright-hand side rear wheel.6 Disconnect the breather hose from the fillerneck (see illustration).7 Disconnect the expansion tank-to-fillerneck hose and breather pipe.8 Disconnect the filler neck funnel which issecured by a large C-clip. 9 Support the fuel tank with a trolley jack andlength of wood. Unscrew the retaining nutsand bolts, detach the straps (see illustration)and lower the tank to the ground. On GTimodels, it will also be necessary to detach theside protector plate.10 If the expansion reservoir is to beremoved, undo the retaining bolt and lower itfrom the wheel arch.11 If the tank is contaminated with sedimentor water, remove the gauge sender unit andswill the tank out with clean fuel. If the tank isdamaged or leaks, it should be repairedprofessionally or renewed.

Refitting12 Refitting is a reversal of removal. Makesure that the rubber packing strips are fittedto the retaining straps. Refit the hoses free ofany kinks.


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6.1 Fuel reservoir location - 1.3 litre

6.3 Fuel reservoir retaining screws(arrowed)

Note earth lead connection to lower screw

7.6 Fuel filler breather valve and hose

7.9 Fuel tank retaining strap-to-floor bolts


7.3 Fuel tank and associated components

8 Fuel gauge sender unit -removal and refitting 2

Warning: The fuel gauge senderunit must always be removed ina well ventilated area.

Removal1 Disconnect the battery negative lead.2 Lift the luggage compartment floor coveringand remove the circular sender unit cover.3 Disconnect the wiring connector from thetop of the unit then detach the fuel supply andreturn hoses.4 Undo the retaining nut and lift out the unit,noting its orientation alignment marking. Asuitable wrench may be necessary to loosenthe securing nut.5 Renew the sender unit seal.

Refitting6 Refit in the reverse order to removal, notingthe following:a) Check that the unit is correctly aligned

with the markings in registerb) Replace the crimped supply and return

line clips with screw type clipsc) Check that the wiring connection is secure.

9 Fuel filler gravity valve -removal, testing and refitting 1

1 The gravity valve is located in the fuel fillerneck and is accessible from within theright-hand rear wheel arch.2 To remove the valve, pull it upwards fromthe fuel filler neck and unclip it.3 When the valve is held vertically, it must beopen. When the valve is angled at 45° then itmust shut. Renew the valve if found to bedefective.4 Refit in the reverse order of removal.

10 Accelerator and throttlecables - removal, refitting andadjustment

2Manual gearbox

Removal1 Disconnect the battery earth lead.2 Remove the air cleaner unit.3 Prise free and release the inner cablesecuring clip(s) at the carburettor throttlecontrol, noting their location (see illustration). 4 Release the cable grommet from thesupport bracket (see illustration).5 Working inside the vehicle, remove thelower facia panel then unclip the inner cablefrom the accelerator pedal (see illustration).6 Withdraw the complete accelerator cableinto the engine compartment, together withthe rubber grommets.

Refitting7 Refitting of the accelerator cable is areversal of removal. Make sure that the cableis free of kinks. Adjust it as follows beforerefitting the air cleaner.

Adjustment8 Before adjusting the cable, check that it iscorrectly aligned over its full length.

9 Have an assistant fully depress theaccelerator pedal.10 Check that the clearance between thethrottle lever at the carburettor and the fully openstop is a maximum of 1.0 mm. Note that thethrottle lever must not be hard against the fullyopen stop (ie. there must be a small clearance).11 There are different cable adjustmentarrangements which are as follows:a) Where locknuts are provided at the

engine end of the outer cable, loosenthem then adjust the cable position andtighten the locknuts

b) Where a ferrule and circlip are provided,extract the circlip, adjust the cableposition then refit the circlip so that it isabutting the ferrule guide

c) On some models, it is necessary to adjustthe inner cable by loosening the clampscrew, repositioning the lever whileholding the cable taut then tightening thescrew

12 After adjustment refit the air cleaner.

Automatic transmission

Removal13 On automatic transmission models, theaccelerator pedal activates the acceleratorcable which is attached to the operating leverof the gearbox shift control. This simul-taneously operates the throttle cable fittedbetween the shift mechanism and thecarburettor (see illustration).14 Before removing either cable, select P(Park).15 To remove the accelerator pedal cable,first loosen the cable adjusting nut thendetach the inner cable from the operatinglever clevis and the outer cable from itslocation bracket. The cable can then bedisconnected from the pedal and removed inthe same manner as that for manual gearboxmodels.16 To remove the throttle cable, loosen theadjuster and locknut at the carburettorsupport bracket, remove the inner cable


10.3 Accelerator cable to carburettor throttle control 10.4 Release cable grommet from support bracket

10.5 Accelerator cable-to-pedalattachment


retaining clip and then disconnect the cablefrom the carburettor.17 At the transmission end, prise free thesecuring clip and detach the cable from theoperating lever and the cable support bracket.

Refitting18 Refitting of both cables is a reversal of theremoval procedure.

Adjustment19 This procedure is described in Chapter7B.

11 Accelerator pedal - removaland refitting 2

Removal1 Remove the lower facia panel.2 Disconnect the accelerator cable from thepedal 3 Prise out the clip and remove the pivot pin.4 Remove the accelerator pedal. If necessarypress out the pivot pin bushes.

Refitting5 Refitting is a reversal of removal. Lubricatethe bushes with a little grease and checkcable adjustment.

12 Choke cable (1.05 litreengine) - removal, refittingand adjustment

2Removal1 Disconnect the battery negative lead.2 Remove the air cleaner.3 Using a screwdriver, loosen the inner andouter cable clamps and disconnect the cablefrom the carburettor.4 Working inside the vehicle, remove thelower facia panel. 5 Pull out the clip and remove the chokeknob.6 Unscrew the ring and withdraw the cablefrom the facia.7 Disconnect the wiring and withdraw thecomplete cable from inside the vehicle.

Refitting8 Refitting is a reversal of removal. Make surethat the cable is correctly aligned and that thegrommets are firmly fitted in the bulkhead.Adjust it as follows before refitting the aircleaner.

Adjustment9 Locate the outer cable in the clamp so thatits end protrudes by approximately 12.0 mm.Tighten the clamp with the outer cable in thisposition (see illustration).

10 Push the choke knob fully in then pull itout by 3.0 mm. Switch on the ignition andcheck that the warning lamp is not lit.11 Insert the inner cable into the choke leverclamp and fully open the choke lever by hand.Tighten the inner cable clamp screw in thisposition.12 Refit the air cleaner.

13 Carburettor - removal andrefitting 3

Removal1 Disconnect the battery earth lead.2 Remove the air cleaner unit.3 Disconnect the accelerator cable from thecarburettor.4 Disconnect the wiring from the following, asapplicable:a) Fuel cut-off solenoidb) Bypass air cut-off valvec) Part throttle channel heaterd) Automatic choke control unite) Earth point

5 Drain off half the engine coolant thendisconnect the coolant hoses from theautomatic choke unit and the expansionelement (where applicable) (see illustrations).6 Disconnect the fuel supply and returnhoses at the carburettor/fuel reservoir, asnecessary, and plug or clamp the hoses toprevent fuel leakage. Note the connections incase of confusion when refitting.7 Disconnect the vacuum hoses and notetheir connections.8 Unscrew the through-bolts or retainingnuts, as applicable, and carefully remove thecarburettor from the inlet manifold (seeillustration).9 To remove the intermediate flange from themanifold, undo the four nuts on the manifoldunderside and lift the flange clear.


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10.13 Accelerator/throttle cable connections – manual gearbox and automatictransmission variants with 2E2 carburettor

12.9 Choke cable adjustment setting –1.05 litre

A Outer cable projectionB Cam and stopC Choke inner cable connection

Refitting10 Refitting is a reversal of the removalprocedure. Ensure that the inlet manifold,intermediate flange and carburettor matingfaces are clean and use new gaskets.

11 On completion, top-up the coolingsystem, restart the engine and check for fueland coolant leaks.12 Adjust the carburettor as necessary.

14 Carburettor - overhaul 41 A complete strip-down of a carburettor isunlikely to cure a fault which is notimmediately obvious without introducing newproblems. If persistent carburation problemsare encountered, it is recommended that theadvice of a VW dealer or carburettor specialistis sought. Most dealers will be able to providecarburettor re-jetting and servicing facilitiesand if necessary, it should be possible topurchase a reconditioned carburettor of therelevant type.2 If it is decided to go ahead and service a

carburettor, check the cost and availability ofspare parts before commencement. Obtain acarburettor repair kit, which will contain thenecessary gaskets, diaphragms and otherrenewable items.3 When working on carburettors, scrupulouscleanliness must be observed and care mustbe taken not to introduce any foreign matterinto components. Carburettors are delicateinstruments and care should be taken not todisturb any components unnecessarily.4 Referring to the relevant exploded view ofthe carburettor (see illustrations), removeeach component part whilst making a note ofits fitted position. Make alignment marks onlinkages, etc.5 Reassemble the carburettor in the reverseorder to dismantling, using new gaskets, O-rings etc. Be careful not to kink anydiaphragms.


13.8 Carburettor securing bolts (arrowed)– Pierburg/Solex 2E3


13.5a Pierburg/Solex 2E3 carburettor, manifold and associatedcomponents

13.5b Pierburg/Solex 2E2 carburettor, manifold and associatedcomponents


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14.4a Pierburg/Solex PIC carburettor components



14.4d Pierburg/Solex 2E2 carburettorcomponents

14.4b Pierburg/Solex 1B3 carburettor top covercomponents

1 Idle speed boosttwo-way valve

2 To idle adjustmentscrews

3 To vacuum lineand brake servo

4 Idling fuel/air jet5 Auxiliary fuel/air jet

6 Choke valve7 Screw8 Cover9 Enrichment tube10 Fuel supply11 Main jet12 Gasket13 Float

14 Needle valve15 Pivot pin16 Pull-down unit17 Adjustment screw18 Automatic choke19 Wiring connector20 Screw

14.4c Pierburg/Solex 1B3 carburettor main body components

1 Bearing ring2 Pump plunger3 Seal4 Injection tube5 Main body6 To pull-down unit7 To air cleaner vacuum control

8 Fast idle adjustment screw9 Part throttle enrichment jet10 Idle speed adjustment screw11 To two-way valve12 Part throttle enrichment valve13 Idle cut-off solenoid14 Mixture adjustment screw


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14.4e Pierburg/Solex 2E3 carburettor components

14.4f Weber 32 TLA carburettor top cover components

1 Screw2 Air correction jet3 Auxiliary fuel jet (if applicable)4 Idling fuel jet5 Emulsion tube6 Choke valve and lever7 Washer8 Gauze filter9 Plugs10 Needle valve11 Pin12 Atomiser13 Gasket14 Float15 Pin16 Main jet17 Pull-down unit18 Automatic choke19 Sealing ring20 Screw21 Heater plate22 Adjusting screw

15 Carburettor (1.05 litreengine) - adjustments 4

Note: Accurate adjustment of the carburettoris only possible if adjustment of the ignitiontiming, dwell angle and spark plug gaps iscorrect. Incorrect valve clearances can alsoeffect carburettor adjustment

Pierburg/Solex 31 PIC7

Bypass air cut-off valve1 To check the bypass air cut-off valve whenremoved, depress the pin approximately 3 to 4mm then energise it with battery voltage. Aclick should be heard and the pin should moveout.

Cut-off valve2 To check the cut-off valve for the main jets(where fitted), apply battery voltage. It must

be heard to click when the voltage is applied.

Choke valve gap3 To adjust the choke valve gap, operate thechoke lever fully then return it to the smoothrunning detent and hold it there. With thechoke spindle lever against the cam, checkthat the clearance between the choke valveand barrel is as shown in Specifications. Use atwist drill to make the check and if necessary,adjust the clearance by turning the adjustingscrew as required (see illustrations).4 Although the choke valve gap smoothrunning detent position is preset duringmanufacture its setting can be checked and ifnecessary adjusted. Pull the choke out fully,then push it onto the smooth running detent.Press the choke lever against the cam andcheck the choke valve gap with a twist drill, asin the previous paragraph. If the gap is not asspecified, adjust by turning the eccentric pinon the choke spindle lever.

Accelerator pump injection capacity5 The accelerator pump injection capacitymay be checked with the carburettor fitted orremoved. However, the air cleaner must beremoved and the float chamber must be full.6 Open the choke valve and retain it in theopen position with a piece of wire, then pusha length of close fitting plastic tube over theinjection pipe. Operate the throttle until fuelemerges then place the tube in a measuringglass. Operate the throttle fully five timesallowing at least three seconds per stroke.Divide the final quantity by five to determinethe amount per stroke and compare with theamount specified. If necessary, reposition theadjusting screw on the accelerator pump lever(see illustration). Note that fuel must beinjected into the throttle valve gap. Ifnecessary, bend the injection pipe.

Slow running and fast idle7 Run the engine to normal operatingtemperature then stop it. Connect atachometer and, if available, an exhaust gasanalyser.8 Check that all electrical accessories areswitched off and note that slow runningadjustments should not be made while theradiator cooling fan is running.9 Disconnect the crankcase ventilation hosefrom the air cleaner body and plug the aircleaner outlet.


15.3a Checking choke valve gap with twistdrill

15.3b Adjusting screw location for chokevalve gap (A) and choke valve gap smooth

running detent eccentric pin (B)15.6 Accelerator pump adjuster screw


14.4g Weber 32 TLA carburettor mainbody components

1 Accelerator pump2 Injection pipe3 Part throttle enrichment valve4 Idle speed boost two-way valve5 To idle adjusting screw6 To vacuum line and brake servo7 Gasket8 Clip9 Idle speed adjustment screw10 Throttle housing11 Sealing ring12 Idle cut-off solenoid13 To air cleaner14 To distributor15 Fast idle adjustment screw16 Mixture adjustment screw

10 Start the engine and let it idle. Check thatthe engine speed and CO content are asspecified. If not, turn the two screws locatedabove the cut-off solenoid alternately asnecessary (see illustration).11 If an exhaust gas analyser is notimmediately available, an approximatemixture setting can be made by turning themixture screw to give the highest enginespeed.12 Reconnect the crankcase ventilationhose. If this results in an increase in the COcontent, the engine oil is diluted with fuel andshould be renewed. Alternatively, if an oilchange is not due, a long fast drive will reducethe amount of fuel in the oil.13 Stop the engine and remove thetachometer and exhaust gas analyser. 14 To adjust the fast idle speed, first checkthat the engine is still at normal operatingtemperature. Remove the air cleaner.15 With the engine stopped, pull the chokecontrol knob fully out then push it in to thesmooth running detent.16 Retain the choke valve in its open positionusing an elastic band. 17 Connect a tachometer then start theengine and check that the fast idle speed is asspecified. If not, turn the adjustment screw onthe side of the choke lever cam. Note that thisscrew may also have a tamperproof cap (seeillustration).18 Stop the engine, disconnect thetachometer and elastic band, then refit the aircleaner. Push the choke control knob fully in.

Pierburg/Solex 1B319 All adjustments are as described for thePierburg 2E3 carburettor fitted to the 1.3 litreengine, with the following additions.

Enrichment tube20 With the choke valve closed, the bottomof the enrichment tube should be 1.0 mmfrom the valve (see illustration).

Idle speed and mixture21 Before making any adjustment, ensurethat the automatic choke is fully open,otherwise the throttle valve linkage may stillbe on the fast idle cam.

Idle speed boost valve22 The idle speed adjustment screw (seeillustration) incorporates a vacuum-operatedvalve which opens if the idle speed dropsbelow 700 rpm, thereby causing an increasein the idle speed. The valve is itself controlledby a two-way valve and further control unit.The control unit monitors the engine speedand activates the two-way valve which appliesvacuum to the idle valve.23 To test the system, run the engine at idlespeed, then slowly reduce the engine speedby manually closing the choke valve. At 700rpm there should be vacuum at the hose inthe idle valve.

Fast idle speed24 With the engine at normal operatingtemperature and switched off, connect atachometer and remove the air cleaner.25 Fully open the throttle valve, then turn the

fast idle cam and release the throttle valve sothat the adjustment screw is positioned on thesecond highest part of the cam.26 Without touching the accelerator pedal,start the engine and check that the fast idlespeed is as specified. If not, turn theadjustment screw on the linkage as necessary.If a tamperproof cap is fitted, renew it aftermaking the adjustment (see illustration).

Choke valve gap27 With the engine cold, fully open the throttlevalve, then turn the fast idle cam and releasethe throttle valve so that the adjustment screwis positioned on the highest part of the cam.28 Press the choke operating rod as far aspossible towards the pull-down unit.29 Using the shank of a twist drill, check thatthe distance from the choke valve to thecarburettor wall is as specified. If not, adjustthe screw behind the automatic choke.

Accelerator pump capacity30 Hold the carburettor over a funnel andmeasuring glass.31 Turn the fast idle cam so that theadjusting screw is off the cam. Hold the camin this position during the following procedure.32 Fully open the throttle ten times, allowingat least three seconds per stroke. Divide thetotal quantity by ten and check that theresultant injection capacity is as specified. Ifnot, loosen the camplate locking screw, turnthe camplate as required and tighten thescrew (see illustration).


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15.10 Idle speed (A) and mixture (B)adjusting screw locations

15.17 Fast idle speed settingA Choke valve held open with rubber bandB Adjustment screw

15.20 Enrichment tube adjustmenta = 1.0 ± 0.3 mm

15.22 Idle speed adjustment screwlocation

15.26 Mixture (CO content) adjustmentscrew location

15.32 Accelerator pump adjustment

1 Nut 2 Camplate locking screw3 Camplate


33 If difficulty is experienced in making theadjustment, check the pump seal and makesure that the return check valve and injectiontube are clear.

Idle cut-off solenoid34 When the ignition is switched on, thesolenoid should be heard to click, indicatingthat the idle circuit has been opened.35 If the solenoid is removed for testing, theplunger must first be depressed by 3.0 to 4.0mm before switching on the unit.

Weber 32 TLA

Float level36 With the upper part of the carburettorinverted and held at an angle of approximately45°, the measurement “a” (see illustration)should be as shown. The ball of the floatneedle should not be pressed in against thespring when making the measurement,

Idle speed and mixture37 The procedure for checking and adjustingthe idle speed and CO content are basicallythe same as given for the Pierburg 31 PIC-7carburettor. Refer to the accompanyingillustrations for the location of adjustmentscrews and to the Specifications for settings.(see illustrations).

Idle speed boost valve38 The idle speed boost valve is identical tothe unit on the Pierburg 1B3 carburettor.

Choke valve gap (pull-down)39 Remove the choke cover.40 Place the fast idle speed adjusting screwon the highest step of the cam (seeillustration). The manufacturer’s originalinstruction was to press the pull rod in thedirection of the arrow shown, then to checkthat the choke valve gap is 2.5 + 0.2 mm. Asfrom April 1987 however, this instruction isrevised and it is now necessary to use avacuum pump to apply 300 mbar vacuum onthe pull-down unit. The choke valve gap inthis case must be 2.0 + 0.2 mm.41 Adjustment is made on the screw at theend of the pull-down device. Ensure that thespring “2” (see illustration) is notcompressed when making the check.

Idle cut-off valve 42 To check the cut-off valve, apply batteryvoltage. The valve must be heard to clickwhen voltage is applied.

Fast idle speed43 Before carrying out this check, ensurethat the ignition timing and manual idlingadjustments are correct. The engine shouldbe at normal operating temperature.44 Remove the air cleaner.45 Plug the temperature regulatorconnection.46 Connect the tachometer.47 Remove the choke cover and set the fast

idle speed adjusting screw on the secondhighest step on the cam (see illustration).48 Tension the operating lever with a rubberband so that the choke valve is fully open.49 Without touching the accelerator pedal,start the engine, which should run at the fastidle speed specified.50 Adjust the screw as necessary.

Choke valve gap (wide open kick)51 Remove the air cleaner.52 Fully open the throttle and hold it in thisposition.53 Press the lever (1) upwards (seeillustration).54 Check the gap with a twist drill. The gapshould be as specified. If necessary, adjust bybending the lever (see illustration).


15.36 Float level checking diagrama = 28 ± 1.0 mm b = 45° angle

15.37a Idle speed adjusting screw (A) -pre June 1985

15.37b Idle speed adjusting screw (A) -from July 1985

15.40 Choke valve gap adjustment

15.37c Mixture (CO content) adjustingscrew (B)

15.41 Checking choke valve gap (pull-down) 15.47 Adjusting fast idle speed

1 Fast idle adjusting screw2 Cam 3 Rubber band

1 Twist drill2 Spring

3 Adjusting screw1 Fast idle adjustment screw2 Cam 3 Pull rod


Accelerator pump capacity55 This can be checked by following theprocedure given for the Pierburg 2E3carburettor, with the following differences.56 Open the throttle valve quickly whenoperating the pump (ie. one second perstroke, with pauses of three seconds betweenstrokes).57 The amount of fuel injected can bealtered, but only very slightly, as follows: (seeillustration).58 Take the accelerator cable cam off thethrottle valve lever.59 Secure the accelerator pump cam with anM4 screw.60 Loosen the locknut on the camplatesecuring screw. Loosen the screw and turnthe camplate with a screwdriver clockwise todecrease injected fuel and anti-clockwise toincrease injected fuel. Tighten the screw andlocknut and recheck the injection capacity.

16 Carburettor (1.3 litre engine)- adjustments 4


Pierburg/Solex 2E3

Cut-off valve1 To check the cut-off valve, apply batteryvoltage. It must be heard to click when thevoltage is applied.

Choke valve gap2 To check the choke valve gap the chokecover must be removed. Move the throttlevalve and the fast idle cam so that theadjustment screw is against the highest camstop. Now push the choke valve operating rodfully towards the adjustment screw (andpull-down unit), then check the chokevalve-to-barrel clearance using a twist drill asa gauge. If necessary turn the adjuster screwas required to provide the specified chokevalve gap (see illustrations).

Accelerator pump injection capacity3 The accelerator pump injection capacitycan be checked in the same manner as thatdescribed for the Pierburg 2E3 carburettor butallow 1 second per stroke and 3 secondsbetween strokes (see illustration).

Choke4 The automatic choke cover and chokehousing alignment marks should correspond.To check the choke, connect up a test lampbetween a battery positive terminal and thechoke lead. The test lamp should illuminate. Ifnot, then the choke unit is defective and mustbe renewed.5 The choke pulldown unit can be checkedwhen removed but as this requires the use ofa vacuum pump and gauge, it is a check bestentrusted to your VW dealer. The pulldownunit can also be tested when the carburettor isin position in the vehicle. The air cleaner unitmust be removed. Run the engine at idlespeed then close the choke valve by hand andcheck that a resistance is felt over the final 3.0mm of travel. If no resistance is felt, there maybe a leak in the vacuum connections, or thepulldown unit diaphragm is broken, in whichcase the unit must be renewed.


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15.53 Checking choke valve gap (wideopen kick)

1 Pressure applied upwards2 Twist drill

15.54 Adjusting choke valve gap (wideopen kick)

Bend lever as required


1 Cam2 Camplate

3 Camplate lockingnut

16.2a Fast idle cam (1) and choke valvegap adjusting screw (2)

16.2b Checking choke valve gap

1 Choke valve operating rod (push indirection of arrow)

2 Twist drill


1 Fast idle camclamp screw

2 Fast idle cam

A Increase capacityB Decrease capacity


Throttle valve6 The basic Stage ll throttle valve adjustmentis made during manufacture and should notrequire further adjustment. If, for any reason,the limiting screw has been removed or itssetting altered, readjust it as follows.7 Open the throttle valve and hold it inposition by inserting a wooden rod or similarimplement between the valve and venturi (seeillustration). Using a rubber band, pretensionthe Stage ll throttle valve locking lever thenunscrew the limiting screw to provide aclearance between the stop and the limitingscrew. Now turn the limiting screw in so that itis just in contact with the stop. The limitingscrew stop point can be assessed by insertinga thin piece of paper between the stop andscrew. When the paper starts to get pinchedbetween the two, the stop point is reachedand from this point, tighten the limiting screwa further quarter turn then secure it withlocking compound. Close both throttle valvesthen measure the locking lever clearances(see illustration). If the clearances are not asspecified, then bend the levers as necessary.

Slow running and fast idle8 To check and adjust the slow runningsetting, refer to Section 15, paragraphs 7 to13 inclusive (see illustration).9 To check and adjust the fast idleadjustment, first check that the engine is stillat normal operating temperature. The air

cleaner must be removed and the otherprovisional conditions must apply as for theslow running adjustment. Plug the air cleanertemperature control hose.10 Restart the engine and open the throttle togive an engine speed of approx. 2500 rpm.Press down the fast idle cam to its stop thenmove the throttle valve back so that theadjuster screw is on the second highest stopon the fast idle cam. In this position, the fastidle speed should be as specified. If thesetting is incorrect, turn the adjustment screwin the required direction until it is correct (seeillustration). Note that the screw may have atamperproof cap fitted.11 On completion, unplug the temperaturecontrol connector and refit the air cleaner.

17 Carburettor (1.6 & 1.8 litreengines) - adjustments 4


Pierburg/Solex 2E21 The adjustment procedures for the 2E2carburettor closely follow those described for

the 2E3 carburettor. The following checks andadjustments are additional to, or differ from,those given.

Part throttle channel heater unit2 To check this unit, connect a test lampbetween the unit wiring plug and batterypositive terminal. Earth the unit. If the testbulb fails to light, the unit is defective andmust be renewed.

Choke valve gap (wide open kick)3 Remove the automatic choke cover and fita rubber band to the operating pin, so that thechoke valve is held in the closed position.4 Hold the primary throttle valve open 45°. Todo this, temporarily insert a 10 mm nutbetween the fast idling adjustment screw andthe vacuum unit plunger.5 Using a twist drill, check that the gapbetween the choke valve and carburettor wallis 6.3 ± 0.3 mm. If not, bend the chokeoperating lever as required (see illustration).6 After making an adjustment, check andadjust the choke pull-down unit as follows.

Choke pull down unit7 This unit can be checked in the samemanner as that for the choke pull down uniton the 2E3 carburettor but note that theresistance felt must be over the final 5.0 mmof travel. 8 Note also that from February 1987, thechoke pull-down unit is both temperature andtime-controlled by a thermotime valve. Whenthe valve is open (starting a cold engine) thevacuum to the pull-down unit is reduced, andthe choke valve will open by a small amount.After between one and six seconds(depending on ambient temperature), thevalve heats up (to approximately 20 to 30°C)and closes. This allows more vacuum to reachthe pull-down unit and the choke valve willopen by a larger amount. The choke is ofcourse fully released by the heat of the enginecoolant and the electric heater acting on theautomatic choke bi-metallic spring.


16.7a Throttle valve basic setting showingrod to hold valve open (arrowed), locklever (1) limiting screw (2) and stop (3)

16.7b Locking lever clearance with throttlevalves closed

Clearance to equal 0.25 to 0.55 mm (each side)

16.8 Idle speed adjustment screw andguide sleeve (A) mixture screw (B)

16.10 Fast idle speed adjustment screw (2)

17.5 Checking choke valve gap

Using drill of correct diameter as a gauge(arrowed)

Note dimension x (10.0 mm)


Accelerator pump9 To make this check, the carburettor mustbe removed and you will need a vacuumpump and an M8 x 20 mm bolt.10 Detach the vacuum hoses from thethree/four point unit then connect up thevacuum pump to the three/four point unit at“A” (see illustration). Plug connection B (andC on four point unit). Apply vacuum with thepump to hold the diaphragm pushrod in theoverrun/cut-off position and to give aclearance between the fast idle speed anddiaphragm pushrod.

11 Pivot the warm-up lever up to the pointwhere the throttle valve control pin hasclearance and insert the M8 x 20 mm bolt tohold the warm-up lever in this position (seeillustration).12 Hold the carburettor over a funnel andmeasuring glass then slowly open the throttlevalve lever fully five times allowing at least 3seconds per stroke. Divide the total quantityby five and check the resultant injectioncapacity against that specified.13 If adjustment is necessary, loosen screwA and rotate the cam plate B in the requireddirection to increase or decrease the injectioncapacity (see illustration). On completion,retighten the screw and seal in position withlocking compound.14 The accelerator pump injection capacitycan also be checked with the carburettor inthe vehicle but as specialised equipment isrequired, this is a task best entrusted to yourVW dealer.

Throttle valve15 For the basic Stage ll valve adjustment,proceed as described in Section 16,paragraphs 6 and 7 whilst referring to theaccompanying illustration (see illustration).

Three/four point unit - vacuum pumpmethod16 Detach the vacuum hoses from the unitand attach a vacuum pump to connection “1”(see illustration). Apply vacuum to pull thediaphragm pushrod to the idle point and thenmeasure the amount of rod protrusion, whichmust be as specified.17 To check the overrun cut-off point, plugoff the vacuum connection 3, then applyincreased vacuum with the vacuum pump.This should cause the diaphragm pushrod tomove to the overrun/cut-off point. Measurethe rod protrusion (a) which should now be1.0 mm. The pushrod should hold at thisposition for one minute.18 If rod protrusion is incorrect, or will nothold for the specified period, then thediaphragm or three/four point unit areprobably leaking and in need of renewal.

Three/four point unit - engine vacuummethod19 Run the engine to normal operatingtemperature then switch it off. Remove the aircleaner and close the vacuum line from thecarburettor to the temperature regulator.20 With the engine stopped, check thediaphragm pushrod (A) (see illustration) isfully extended to approximately 14.5 mm.21 Start the engine and let it idle. Thediaphragm pushrod must now be extendedapproximately 8.5 mm (three-point unit), or9.5 mm (four-point unit), and must justcontact the fast idle adjustment screw.22 On models with air conditioning, switchon the air conditioner with the blower onmaximum speed. The diaphragm pushroddimension should be approximately 12.0 mm.23 To check the overrun cut-off point, run theengine at idle speed.24 On the four-point unit, disconnect andplug the pink-coloured hose at the controlvalve.25 Using a screwdriver, hold the primarythrottle valve fully closed to prevent it movingto the overrun cut-off point.26 Disconnect the plug from theidling/overrun control valve, then check thatthe diaphragm pushrod dimension isapproximately 1.5 mm.27 To check the unit for leaks, first, on thethree-point unit only, pinch the hose betweenthe unit and Y-piece.


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17.10 Accelerator pump checkpreparation

A Vacuum pump connectionB Plug vacuum connection (3-point unit)C Plug vacuum connection (4-point unit)

17.11 Accelerator pump adjustment checkshowing warm-up lever (A) lever (B) and

bolt (C)

17.13 Loosen screw (A) and turn cam plate(B) in direction required to adjust

accelerator pump injection capacity

17.15 Lock lever clearance with throttlevalves closed

17.16 Three or four point unit checkpreparation

Pushrod to idle point a = 8.5 mm1 Vacuum connection2 and 3 Plug these connections

17.20 Three/four point unit with pushrod(A) and cold idling adjusting screw (B) in

idling position


28 Stop the engine by disconnecting the coilterminal 15, and check that the diaphragm rodremains in the overrun/cut-off position for aminimum of five seconds.29 Reconnect the coil wiring, control valveplug and hose where applicable. Refit the aircleaner.

Stage ll vacuum control unit30 This device is fitted to 1.6 litre manualgearbox models and 1.8 automatic gearboxmodels from August 1984 on. Its function is todelay the Stage ll opening slightly whilst thecoolant temperature is below 18°C. Itachieves this by venting the vacuum hose viathe thermo-pneumatic valve and the resistor(see illustration).31 Check that the straight hose at connection3 on the thermo-pneumatic valve is notblocked and check the valve itself by blowingthrough it. It should be open at 18°C and closewhen the temperature rises above 28°C.

Idle/overrun control valve32 Entrust this operation to your VW dealer asspecialised testing equipment is necessary.

Temperature time valve33 Entrust this operation to your VW dealeras specialised testing equipment isnecessary.

Slow running and fast idle34 To check and adjust the slow runningsetting, proceed as described in Section 15,

paragraphs 7 to 13 inclusive whilst noting thefollowing differences:a) Before making any adjustments, ensure

that the three/four point unit pushrod is inthe idling position with the cold idlingadjusting screw touching the pushrod

b) If adjustment is necessary, turn the idlingspeed control valve and CO adjustmentscrew (see illustrations), as necessary.

c) Access to the CO adjustment screw isgained by prising out the tamperproofplug. If the CO content is difficult toadjust, remove the adjustment screw andclean its point, then refit and adjust it

35 On automatic transmission models, theincreased idling speed can be checked andadjusted as follows. In addition to thosepreliminary requirements necessary whenchecking the idle speed slow running setting,the hand brake must be fully applied andchocks placed against the wheels.36 When the engine is started, turn on thefresh air blower (fully), switch on the headlights(high beam) and the heated rear window. Getan assistant to sit in the vehicle and depressthe foot brake then select D. Check that thefour point unit diaphragm rod is in theincreased idling position, the fast idle adjusterscrew rests against the diaphragm rod and theengine increased idle speed is not under thatspecified. Adjust if necessary by altering theregulator valve setting (see illustration).37 On models fitted with air conditioning, theprocedure for checking the increased idlingspeed is similar to that for automatic

transmission models except that it is alsonecessary to switch on the air conditioner andhave the control set at maximum cooling atthe highest blower speed. The increased idlespeed must be as specified and if adjustmentis required, alter the regulator valve settingaccordingly.38 With the slow/increased running idlespeed adjustment complete, the fast idlespeed can be checked and, if necessary,adjusted. Check that the engine is still at itsnormal operating temperature.39 Detach the Y-piece from the vacuum hoseand plug the hose (see illustration). Connecta tachometer to the engine. Start and run theengine and check that the fast idle speed is asspecified. If not, turn the adjustment screw onthe linkage as necessary (see illustration). Oncompletion of adjustment, apply sealant tothe screw threads to lock it in position, unplugand reconnect the Y-piece to the vacuumhose and check that the slow running (idle)speed is as specified.

18 Inlet manifold preheating -testing 2

Heater element1 The inlet manifold is preheated by coolantfrom the cooling system and by a heaterelement located in the bottom of the inletmanifold.


17.30 Stage II vacuum unit control

1 Thermo-pneumatic valve2 Restrictor3 Straight connection hose

17.34a Idling speed control valve (A) 17.34b Mixture (CO) adjustment screw (A)

17.36 Engine speed regulator valve (1) 17.39a Disconnect and plug vacuum hose(1) to check/adjust engine fast idle speed

adjustment

17.39b Fast idle adjustment screw (A)


2 To check the heater element, the engineshould be cold. Disconnect the wire from theelement at its in-line connector, then attach anohmmeter between the wire connector fromthe element and earth. This should record0.25 to 0.50 ohm.3 To remove the element, disconnect the wirethen unscrew the bolts and withdraw the unit.Remove the sealing ring and gasket (seeillustrations). When refitting, always renewthe sealing ring and gasket.

Thermo-switch4 On 1.05 and 1.3 litre engines, the heaterelement is controlled by a thermo-switchlocated in the coolant supply hose to the inletmanifold. On 1.6 and 1.8 litre engines, thethermo-switch is located in the top of thecoolant hose connecting piece mounted onthe side of the cylinder head.

5 Before removing the thermo-switch, drainoff some engine coolant to reduce spillagewhen the switch is removed.6 To test the thermo-switch, first detach thelead connector. Unscrew and remove theswitch from the housing and plug the hole tostop any leakage of coolant.7 With an ohmmeter connected to theterminals, gradually heat the base of theswitch unit in hot water. Below the followingtemperatures there should be zero resistance(ie. internal contacts closed):

1.05 litre engine - 65°C1.3, 1.6 and 1.8 litre engines - 55°C

8 Above the following temperatures thereshould be a maximum resistance (ie. internalcontacts open):

1.05 litre engine - 75°C1.3, 1.6 an d 1.8 litre engines - 65°C

9 If defective, the switch must be renewed.

19 Inlet and exhaust manifolds -removal and refitting 3

Inlet manifold1 Remove the carburettor.2 Disconnect the inlet manifold preheaterwire at the in-line connector.3 Drain the cooling system and disconnectthe coolant hoses from the manifold.4 Disconnect the manifold vacuum hoses asnecessary (see illustration).5 Where applicable, disconnect the stay rodbetween the base of the manifold and thecrankcase (see illustration).6 Undo the manifold retaining nuts and bolts(see illustration) whilst noting their respective


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18.3a Unscrew the bolts . . . 18.3b . . . and remove heater element frominlet manifold

18.3c Removing sealing ring from heaterelement


19.4 Vacuum hose connections – 1.6 and 1.8 litre withPierburg/Solex 2E2 carburettor

locations, then carefully withdraw themanifold from the cylinder head.7 Remove the gasket and clean the matingfaces of the manifold and cylinder head.8 Refitting is a reversal of the removalprocedure. Use a new manifold gasket andtighten the securing nuts and bolts to thespecified torque setting.

Exhaust manifold9 Undo the retaining nut(s) and withdraw thewarm air deflector plate from the exhaustmanifold (see illustration).10 On 1.05 and 1.3 litre engines, unbolt anddetach the exhaust downpipe from themanifold joint (see illustration).11 On 1.6 and 1.8 litre engines, refer toSection 20, paragraph 2.12 Unscrew and remove the remainingmanifold retaining bolts/nuts, then carefullywithdraw the manifold from the cylinder head.Remove the gasket.13 Clean the mating faces of the manifoldand cylinder head. Also the exhaust downpipeflange connections.14 Refit in the reverse order of removal. Usea new gasket and tighten the securingnuts/bolts evenly to the specified torquewrench setting.15 When reconnecting the downpipe to themanifold, smear a little exhaust jointing pasteonto the flange prior to connection. This willensure a good seal at the joint.

20 Exhaust system - inspection,removal and refitting 3

Inspection1 Refer to Chapter 1, Section 19

Removal2 On 1.6 and 1.8 litre engines, it should benoted that if the exhaust system is to beseparated at the manifold/downpipeconnection, then VW tool No. 3049A will benecessary to release and subsequently refitthe joint retaining clips (see illustration).Without this tool, it is virtually impossible toseparate and reassemble the joint withoutdistorting the retaining clips. In view of this,removal and refitting of the system willnecessitate detachment of the manifold andfront pipe section, or manifold and systemcomplete, and then taking the assembly toyour VW dealer to separate/reassemble thefront joint. If the complete system is in need ofreplacement, it is probably best entrusted toyour VW dealer. 3 On 1.05 and 1.3 litre engines, whenremoving any part of the exhaust system it isusually easier to undo the manifold-to-frontpipe joint and remove the complete systemfrom the vehicle, then separate the various

pieces of the system, or cut out the defectivepart with a hacksaw.4 Before doing any dismantling work on theexhaust system, wait until the system is cooland then saturate all bolts and joints with aproprietary anti-corrosion fluid (seeillustrations). It may be found easier to cutthrough heavily corroded bolts with ahacksaw, rather than try to unscrew them.

Refitting5 Refit the system a section at a time startingat the front. If the manifold has been removedits gasket must be renewed. New nuts andbolts should be used throughout the system.6 Before assembly, smear all joints with aproprietary exhaust sealing compound. Thismakes it easier to align the pieces and alsoensures that the joints will be gas tight. Leaveall bolts loose.7 Run the engine until the exhaust system isat normal temperature and then, with theengine running at idling speed, tighten all themounting bolts and clips, starting at themanifold and working towards the rearsilencer. Take care to avoid touching any partof the system with bare hands because of thedanger of painful burns.8 With all bolts and clips tightened, it isimportant to ensure that there is no strain onany part of the system.


19.5 Inlet manifold support stay - 1.3 litre 19.6 Inlet manifold-to-cylinder headsecuring nuts and bolts

Note position of earth lead spade connector(arrowed) - 1.3 litre

19.9 Warm air deflector plate - 1.3 litre

19.10 Exhaust downpipe-to-manifoldflange connection - 1.3 litre

20.2 VW tool 3049A used to release and fitexhaust downpipes to manifold clips -

1.6 and 1.8 litre



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20.4b Exhaust system and associated components – 1.6 and 1.8 litre

Connecting piece and clamp setting dimensions

a = 5.0 mmb = 12.0 mmc Marking (S for manual gearbox or A for automatic

transmission)

20.4a Exhaust system and associated components – 1.5 and 1.3 litre

Connecting piece and clamp setting dimensions

a = 5.0 mm b = 12.0 mm c Marking (S)

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Notes

Documents

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