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Edition 08.96
Removing and installing fuel delivery unit
Pay attention to safety precautions ⇒
page 20-4.
Pay attention to rules for cleanliness ⇒ page
20-4. Special tools, testers and aids required♦ Wrench for union nut MP 1-227
Removing
- If car is fitted with a coded radio set, deter- mine coding, if necessary.
- Switch off ignition (if not already off) and dis- connect earth strap at the battery.
- Unbolt cover (below the rear seat).
- Disconnect feed and return flow pipes from the flange of the fuel delivery unit (press release buttons).
- Release 4-pin connector from the flange at the fuel tank and unplug.
- Use wrench MP 1-227 to unscrew union nut.
- Pull fuel delivery unit and seal out of the
opening of the fuel tank.
Note:
If the delivery unit is still filled with fuel, emptybefore replacing.
Installing Installation is performed in the reverse order; pay attention to the following points:
Notes:
♦When inserting the fuel delivery unit, ensure
that the fuel gauge sender is not bent.
♦Moisten seal of the flange with fuel beforeinstalling.
♦Ensure the fuel hoses are tightly connected.
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20Fuel Supply System
Edition 08.96
- Pay attention to installation position:
Marking on the flange should be aligned with the marking on the fuel tank -arrows-.
Blue return flow pipe -1- to connectionwith marking -R-.
Black feed pipe -2- to connection with marking -V-.
Removing and installing fuel gauge sender
Removing
- Remove fuel delivery unit page 20-5.
- Release connector tabs of cables -3- and -4-
and unplug.
- Use a screwdriver to lift the retaining tabs -1- and -2- and pull fuel gauge sender down
and off -arrow-.
Installing
- Insert fuel gauge sender into the guides at the fuel delivery unit and push up until it locks in place.
Removing and installing fuel tank
Pay attention to safety precautions page 20-4.
Pay attention to rules for cleanliness page
20-4 Special tools, testers and aids required Engine/gearbox jack (e.g. V.A.G 1383 A)
Fuel extraction unit (e.g. V.A.G 1433 A)
Page 123 of 136
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Removing
- If car is fitted with a coded radio set, pay attention to coding; determine if necessary.
- Switch off ignition (if not already off), and disconnect earth strap at the battery.
- Empty fuel tank with fuel extraction unit (e.g. V.A.G 1433 A).
- Remove rear suspension: ⇒ Running Gear; Repair Group 42; Servicing rear suspension; Removing and installing rear suspension.
- Unbolt cover (below the rear seat).
- Release 4-pin connector from the flange at fuel tank and unplug.
- Open fuel filler flap and lever out tensioning ring in rubber bowl (around filler neck).
- Push rubber bowl through to the inside.
- Remove rear right wheelhouse liner.
- Unscrew fuel filler neck below the wheel- house liner.
- Remove cover below the fuel tank -arrows-
(if fitted).
- Disconnect return flow pipe -2- (blue), feed
pipe -1- (black) and breather pipe -3- (white) at the front right of the fuel tank (press release buttons).
- Place engine/gearbox jack (e.g. V.A.G 1383 A) below the fuel tank to support it.
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20Fuel Supply System
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- Detach screw connections -arrow- at the
front left and at the retaining straps.
- Lower fuel tank. Installing Installation is performed in the reverse order; pay attention to the following points:
- Connect fuel pipes to the flange of the fuel
delivery unit:
Blue return flow pipe -1- to connection marked with -R-.
Black feed pipe -2- to connection marked with -V-.
Connecting remote control
Special tools, testers and aids required Remote control V.A.G 1348/3A with adapter
cable V.A.G 1348/3-2
Procedure
- Open cover of the fuse box on the left-hand side of the dash panel.
- Remove fuse 28 at the fuse carrier (left-hand row, 5th large fuse form the top).
- Connect remote control V.A.G 1348/3A with
adapter cable V.A.G 1348/3-2 to the fuse base of fuse 28 -arrow-.
- Connect clamp to car battery (+).
Page 125 of 136
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Testing fuel pump
Special tools, testers and aids required
Hand-held multimeter (e.g. V.A.G 1526)
Wrench for union nut (e.g. MP 1-227)
Adapter cable set (e.g. V.A.G 1594)
Current flow diagram
Test conditions
Holding pressure o.k.; testing:
1.8 ltr./92 kW Engine, Motronic Fuel Injection and Ignition System; Repair Group 24;
Testing fuel pressure regulator and holding pressure
Battery voltage at least 12 V
Fuse 28 o.k.
Fuse filter o.k.
Test procedure
- Switch on ignition. The fuel pump should be heard to operate. (A second mechanic may be required if there is a high level of surrounding noise) If the fuel pump does not run:
- Switch off ignition.
- Connect remote control V.A.G 1348/3A with adapter cable V.A.G 1348/3-2 page 20-8.
- Operate remote control.If the fuel pump runs:
Test fuel pump relay: 1.8 ltr./92 kW Engine, Motronic Fuel Injection and Ignition System; Repair Group 24; Servicing Motronic fuel injection system; testing fuel pump relay and actuation
Page 126 of 136
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20Fuel Supply System
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If the fuel pump does not run:
- Unbolt cover (below the rear seat).
- Release 4-pin connector form the flange at
the fuel tank and unplug.
- Connect hand-held multimeter (e.g. V.A.G
1526) with auxiliary cables (e.g. from V.A.G
1594) to the outer contacts of the connector.
- Operate remote control. Specification: about battery voltage
If the specification is not achieved:
- Determine open circuit in the wiring on the basis of the current flow diagram and rectify:
⇒ Current Flow Diagrams, Electrical Fault Finding and Fitting Locations binder
If the specification is achieved:
- Use MP 1-227 to unscrew union nut.
- Check whether the electric cables between flange and fuel pump are connected and test
for continuity.
If no open circuit in the wiring can be found:
Fuel pump faulty.
- Replace fuel delivery unit ⇒ page 20-5.
Testing delivery of the fuel pump
Special tools, testers and aids required♦ Adapter V.A.G 1318/17
♦ Measuring vessel
Test conditions
Battery voltage at least 12 V
Voltage supply o.k.
Fuel filter o.k.
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Test procedure
- Switch off ignition.
- Connect remote control V.A.G 1348/3A with
adapter cable V.A.G 1348/3-2 ⇒ page 20-8.
- Remove cap from the fuel filler neck.
Important! Fuel system is pressurised! Place cleaning ragsaround the connection point before opening the
system. Then, release pressure by carefullyloosening the connection point.
- Disconnect fuel return flow pipe -2- (press
release buttons).
- Connect auxiliary hose to adapter V.A.G 1318/17 and fit onto the fuel return flow pipe of the engine and hold in a measuring vessel.
- Operate remote control for 15 seconds (press button and hold).
- Compare quantity of fuel supplied with spe-
cification.
*)Minimum delivery cm3/15 s
**)Voltage at fuel pump when engine switched
off and pump running (about 2 V less than battery voltage).
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20Fuel Supply System
Edition 08.96
1 - Solenoid valve 1 (N80)
Testing operation and actuation:
1.8 ltr./92 kW Engine, Motronic Fuel Injection and Ignition System; Repair Group 24;
Testing tank breather; Testing solenoid valve 1 for activated charcoal filter
2 - Connector
3 - Vent pipe From gravity valve at fuel tank page
20-2, item 4
To disconnect, press release buttons on connector
4 - Throttle valve control unit
5 - Activated charcoal filter with solenoid valve 1 (N80)
Installation point: in right of engine compartment
To remove, take off PAS reservoir andpush to the side
6 - Spring nut
Removing and installing parts of the activated charcoal filter system Servicing throttle mechanism
1 - Throttle cable Adjust by re-positioning locking ele- ment on detent page 20-13
2 - Locking element
3 - Accelerator pedal
4 - Spacer bush
5 - Bearing bush
6 - Washer
7 - Stop screw
8 - 20 Nm
