Fuel Delivery Unit
Fuel Delivery Unit
Special tools, testers and auxiliary items required
• Union nut tool (T40068 A)
Removing
Observe safety precautions. Refer to => [ Safety Precautions ] Fuel Supply System.
Observe rules for cleanliness. Refer to => [ Clean Working Conditions ] [1][2]Fuel Injection System.
CAUTION!
Danger due to escaping fuel.
• To prevent large quantities of fuel from leaking from the fuel delivery unit when removing, the fuel tank may only be a maximum of 1/4 full. Drain fuel tank if necessary. Refer to => [ Fuel Tank, Draining ] Procedures.
- If necessary, move front seats completely forward.
CAUTION!
Risk of destroying electrical components when battery is disconnected.
• Follow the instructions when disconnecting the battery.
- Switch off ignition.
Sedan:
- Fold the luggage compartment floor upward.
Wagon:
- Remove luggage compartment cargo floor - 1 - and spare wheel cover - 2 -.
All:
- Release the retaining clips - arrows - with a screwdriver - 2 - and remove the cover - 1 -.
- Disconnect ground (GND) strap at battery ground (GND) terminal - arrow -.
- Remove rear seat bench.
- Unbolt cover for right locking flange - arrows -.
- Disconnect electrical harness connector - arrow - at right locking flange.
- Mark the fuel supply line - 1 - and fuel return line - 2 -.
CAUTION!
There is a risk of injury because the fuel is under high pressure.
• To reduce pressure in fuel system, lay a clean cloth around the connector and carefully loosen connector.
- Pull both lines from locking flange, by pressing the release buttons.
CAUTION!
Danger due to escaping fuel.
• To prevent large quantities of fuel from leaking from the fuel delivery unit when removing, the fuel tank may only be a maximum of 1/4 full.
- Remove the union nut with the (T40068 A) - arrow -.
• The plastic catch on the threaded ring breaks off when the union nut is loosened.
- Pull right locking flange of fuel delivery unit out of opening in fuel tank and set aside with lines still connected.
- Through the opening in the fuel tank, disconnect electrical harness connector - 2 - for fuel level sensor 2.
- Disconnect the suction jet pipe - 1 - to suction jet pump by pressing release button.
- Disengage the fuel delivery line - 3 -.
- Remove fuel delivery unit.
• When removing fuel delivery unit, be sure not to bend floater arm of fuel level sensor.
• Be aware that fuel is still in the fuel delivery unit.
Installing
• Assembly overview, refer to => [ Fuel Delivery Unit and Fuel Level Sensor Assembly Overview ] Fuel Delivery Unit and Fuel Level Sensor Assembly Overview.
• Tightening specifications, refer to => [ Fastener Tightening Specifications ] Fuel Supply System - Fastener Tightening Specifications.
Installation is performed in the reverse order of removal, noting the following:
• Always replace seal and union nut.
• When inserting fuel delivery unit, be sure not to bend floater arm of fuel level sensor (G).
• Ensure fuel hoses are seated securely.
- Insert fuel delivery unit into fuel tank with locking flange set aside.
- Attach the fuel delivery line - 1 -.
- Push the suction jet pipe - 4 - onto the suction jet pump until it engages audibly.
- Connect electrical connector - 3 - for fuel level sensor 2.
- Slide the new gasket - 2 - over the sealing flange and insert it in the groove on the fuel tank.
- Make sure the fuel lines and electrical wires are routed correctly:
• Route the fuel supply line - 1 - between the guide tube - 4 - and the supports - 2 - for the fuel return line. Also, it must be routed around the outside of the guide tube - 3 -.
- Insert the guide tubes - 3 - and - 4 - of the locking flange into the guide holes - arrows - of the fuel delivery unit.
• To improve clarity, the fuel delivery unit is shown without the fuel tank.
- Slide the fuel supply line clockwise - away from the fuel level sensor movement area - under the sealing flange.
- Slide the union nut - 1 - over the left arm and press the sealing flange forcefully - 2 - into the installation position with the left hand - arrow -.
• The tab - 4 - on locking flange must lie between tabs - 3 - and - 5 - on threaded ring.
- With the right hand, slide the union nut - 1 - off the left arm while continuing the press the sealing flange - 2 - down forcefully with the left hand - arrow -.
- Position the union nut - 1 - with the right hand so the double ridge - 5 - on the ribbing lies over the tab - 3 - on the sealing flange (approximately the 10 o'clock position). This makes sure the union nut engages at the beginning of the threads immediately when tightening it - 4 -.
- Continue pressing the sealing flange down forcefully.
- Rotate the sealing ring approximately 390° with the right hand until the double ridge - 1 - is in the 12 o'clock position while continuing to press the sealing flange down forcefully with the left hand.
CAUTION!
There is a risk of the locking flange threaded connection leaking.
• Press the locking flange down firmly when tightening the union nut so it does not rotate too.
- Tighten the right sealing flange union nut with the (T40068 A).
• Verification: The double ridge - 1 - must now be between the 5 o'clock and 6 o'clock positions.
- Install fuel supply line - 1 - and the fuel return line - 2 - according to the marking.
- Connect electrical harness connector.
- Install rear seat bench.
- Connect battery. Observe safety precautions after connecting battery.
- Fill vehicle with at least 5 liters of fuel after installing fuel level sensor.