GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1999 🢒 Eldorado 🢒 Engine 🢒 Engine Controls - 4.0L and 4.6L 🢒 Fuel Tank Replacement

Tools Required
  1. J 34730-1A Fuel Pressure Gauge
  2. J 39765 Fuel Sender Locknut Wrench

Removal Procedure

    Object Number: 243761 Size: SH
  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  2. Raise the vehicle and suitably support. Refer to Lifting and Jacking the Vehicle in general information.
  3. Drain the fuel tank. Refer to Fuel Tank Draining .

    4. Important: If nylon fuel feed or return pipes become kinked, and cannot be straightened, they must be replaced.

  4. Disconnect the fuel feed pipe (1) at the in-line fuel filter and return pipe (2) near the in-line fuel filter.

    5. Object Number: 157703 Size: SH
  5. Grasp both ends of the fuel feed pipe connection and twist 1/4 turn in each direction to loosen any dirt in quick connect fittings.

    6. Caution: Wear safety glasses when using compressed air in order to prevent eye injury.


    Object Number: 155410 Size: SH
  6. Blow out dirt from quick connect fittings, using compressed air.

    7. Object Number: 12777 Size: SH
  7. Squeeze the plastic tabs of male end connector of fuel filter.

    8. Object Number: 12778 Size: SH
  8. Pull connection apart.
  9. Repeat steps 5 through 8 for the other fitting.

    10. Object Number: 20376 Size: SH
  10. Disconnect the clamps (3) at the fuel filler neck (2) and fuel filler neck vent pipe (1) at the fuel tank (4).
  11. Remove the fuel filler neck (2) and fuel filler neck vent pipe (1) from the fuel tank (4).

    12. Object Number: 237458 Size: SH
  12. Disconnect the fuel sender (1) electrical connector.
  13. Remove the exhaust heat shield screws and reposition shield.

    14. Notice: Do not bend the fuel tank straps as this may damage the straps.

  14. Support the fuel tank and remove the fuel tank retaining strap bolts (2) from the fuel tank retaining strap (3).
  15. Lower the fuel tank and disconnect the EVAP pipe.
  16. Inspect the connectors for dirt and damage. Clean or replace as required.
  17. Remove the fuel sender assembly (1) from the fuel tank using J 39765 Fuel Sender Lock nut Wrench. Refer to Fuel Sender Assembly Replacement .

Installation Procedure

    Object Number: 237458 Size: SH

    Important: Always install a new lip seal when servicing the modular fuel sender assembly.

  1. Lightly lubricate the inside diameter of the lip seal with clean engine oil.
  2. Install fuel sender assembly (1) into the fuel tank (4) using J 39765 Fuel Sender Lock nut Wrench. Refer to Fuel Sender Assembly Replacement .

    3. Important: Assure proper location of fuel sender pipes.

  3. Install fuel tank retaining straps (3) attaching bolts (2) with the aid of an assistant to the fuel tank (2).
  4. Raise the fuel tank and connect EVAP pipe.

    5. Tighten
    Tighten the fuel tank strap bolts to 42 N·m (31 lb ft).

    Refer to the

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

    in Cautions and Notices.

  5. Install exhaust heat shield screws.
  6. Connect the fuel sender electrical connector.

    7. Object Number: 20376 Size: SH
  7. Install the fuel filler neck (2) and fuel filler neck vent pipe (1) at the fuel tank (4).
  8. Install the clamps (3) at the fuel filler neck (2) and fuel filler neck vent pipe (1).

    9. Tighten
    Tighten the clamps to 4.3 N·m (38 lb in).

    Caution: Always apply a few drops of clean engine oil to the male pipe ends before connecting the fuel pipe fittings in order to reduce the risk of fire and personal injury. This will ensure proper reconnection and prevent a possible fuel leak. During normal operation, the O-rings located in the female connector will swell and may prevent proper reconnection if not lubricated.


    Object Number: 155425 Size: SH
  9. Apply a few drops of clean engine oil to the male connector pipe ends.

    10. Object Number: 155771 Size: SH
  10. Push connectors together to cause the retaining tabs/fingers to snap into place.

    11. Object Number: 155399 Size: SH
  11. Pull on both ends of each connection to make sure connection is secure, once installed.

    12. Object Number: 235992 Size: SH
  12. Lower the vehicle.
  13. Reinstall the fuel filler cap.
  14. Add fuel to the fuel tank.
  15. Connect the negative battery cable. Refer to

    Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

    .
  16. Inspect for fuel leaks.
    17. 16.1. Turn ignition switch to ON for 2 seconds.
    16.2. Turn the ignition switch to OFF for 10 seconds.
    16.3. Turn the ignition switch ON.
    16.4. Check for fuel leaks.
  17. Reinstall the intake manifold sight shield. Refer to Intake Manifold Removal in engine mechanical.