AWD

Removing and installing fuel pump


CAUTION: To remove the Fuel Pump (FP), the fuel tank may only be filled to a maximum of 1/4. Empty fuel tank if necessary.


Recommended special tools and equipment







- 3087 wrench for tank sensor







- Fuel Pump Wrench 3307







- VAS5190 fuel siphoning device

Empty fuel tank
Observe safety precautions.
Observe rules for cleanliness.


CAUTION: Observe safety precautions when disconnecting the battery.


- Disconnect battery Ground (GND) strap with the ignition switched off.


CAUTION: Secure Ground (GND) wire of VAS5190 to a blank portion of the chassis.







- Pull cone piece -2- from shaft piece -1- of VAS 5190.
- Using insulating tape, apply a mark -arrow- on hose at length a = 1,865 mm from end of suction hose.
- Remove fuel filler cap from fuel filler tube.







- Screw shaft piece -1- of VAS 5190 fuel siphoning device on to fuel filler tube of fuel tank.
- Now slide suction hose as far into fuel tank until the mark applied earlier -arrow- stands on shaft piece.

NOTE:
- If using a siphoning device without shaft piece, proceed principally in the same manner.







- In this case, apply a mark -arrow- on hose at length a = 1,800 mm from end of suction hose using insulating tape. The suction hose is inserted correctly when the marking applied earlier stands opposite the lip of fuel filler tube.
- If the hose can only be inserted with difficulty, smear it thinly with engine oil. Never use lubricants containing silicon.


- Drain fuel tank through fuel filler tube as much as possible.
- Carefully remove siphoning hose.
- Remove rear seat bench.







- Remove cover for right connector flange (arrows).







- Carefully disengage and disconnect electrical harness connector -1- (right side of vehicle).
- Disengage electrical harness connector -2- and lay it aside.


CAUTION: Fuel system is under pressure. Before opening system, place rags around the connection area. Then release pressure by carefully loosening connection.







- Disconnect fuel supply line -1- from connector flange (right side of vehicle).
- Disconnect ventilation line -2- (press release button).







- Use 3087 wrench to remove locking ring.
- Pull connector flange and sealing ring from opening of fuel tank.







- Disconnect harness connector -arrow- to fuel gauge on the inside of connector flange.







- Slide suction hose for a length of dimension x = 800 mm through right opening on fuel tank to left tank chamber.
- Empty left fuel tank chamber.
- Remove rear seat bench.






- Remove cover for right connector flange (arrows).







- Carefully disengage and disconnect electrical harness connector -1- (right side of vehicle).
- Disengage electrical harness connector -2- and lay it aside.


CAUTION: Fuel system is under pressure. Before opening system, place rags around the connection area. Then release pressure by carefully loosening connection.







- Disconnect fuel supply line -1- and ventilation line -2- from connector flange (right side of vehicle) (press release button).







- Use e.g. 3087 wrench to remove locking ring.
- Pull connector flange and sealing ring from opening of fuel tank.







- Disconnect harness connector -arrow- to fuel gauge on the inside of connector flange.







- Guide fuel pump wrench 3307 in through fuel tank opening and position on Fuel Pump (FP).
- Rotate Fuel Pump (FP) toward left approx. 15 degrees to stop.







- Notch -1- aligns with marking -2- (bayonet connection)

- Remove Fuel Pump (FP).

Installing
Installation is the reverse of removal, noting the following:
- Insert new, dry seal for connector flange from fuel level sensor 2 into opening of fuel tank.







- Note the installation position of connector flange from fuel level sensor 2:
- The tab -2- on connector flange must lie between tabs -1- and -3- on fuel tank.


NOTE: Arrow points in direction of travel.







- Tighten locking ring.







- Insert Fuel Pump (FP) into baffle housing in tank so that the notch -1- at the Fuel Pump (FP) aligns with the marking -2- at the baffle housing.
- Fuel Pump (FP) can be pressed downward significantly and noticeably







- Guide fuel pump wrench 3307 in through fuel tank opening and position on Fuel Pump (FP).
- Rotate Fuel Pump (FP) toward right approx. 15 degrees to stop.







- Notch -1- aligns with marking -3- (bayonet connection)







- Connect harness connector -arrow- for fuel gauge on inside of connector flange.
- Insert new, dry seal for connector flange into opening of fuel tank.







- Note installation position of connector flange:
- The tab -2- on connector flange must lie between tabs -1- and -3- on fuel tank.


NOTE: Arrow points in direction of travel.







- Tighten locking ring.
- Observe safety precautions after connecting the battery.

Tightening torques

Component Nm
Locking ring for Fuel Pump (FP) or connector flange of fuel level sensor 2 145
Battery terminal to battery post 6

Final procedures
After re-connecting the voltage supply, the following work steps must be performed in the mentioned sequence:
1 - Vent fuel system.
2 - Check DTC memory, see "Mode 3: Check DTC memory".
3 - If necessary, erase DTC memory, see "Mode 4: Reset/erase diagnostic data".
4 - Generate readiness code.

- End diagnosis and switch ignition off.