GM Service Manual Online
For 1990-2009 cars only

Caution: Gasoline or gasoline vapors are highly flammable. A fire could occur if an ignition source is present. Never drain or store gasoline or diesel fuel in an open container, due to the possibility of fire or explosion. Have a dry chemical (Class B) fire extinguisher nearby.

Tools Required

J 42374 Fuel Line Quick-Connect Separator Tool Set

The following procedure covers the disassembly and the inspection of the complete fuel supply system. If the fuel system is contaminated, the fuel system can be cleaned. You can usually determine the extent of the fuel system contamination during the disassembly.

    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.

  1. Disconnect the negative battery terminal.
  2. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  3. Remove the in-line fuel filter. Refer to In-Line Fuel Filter Replacement .
  4. Inspect the fuel system for contamination of the in-line fuel filter.
  5. Replace the filter after cleaning the fuel lines if the filter is plugged or contaminated.

  6. Drain the fuel tank. Refer to Fuel Tank Draining .
  7. Remove the fuel tank. Refer to Fuel Tank and Evaporation Emission Canister Replacement .
  8. Locate the tank in a suitable work area away from any heat, any flame or any other source of ignition.
  9. Remove the fuel sender assembly.
  10. • Inspect the fuel sender strainer. If strainer is contaminated, you must clean the strainer and clean the fuel tank.
    • Inspect the fuel pump inlet for dirt and debris. Replace the fuel pump if dirt or debris is found.
  11. Flush the fuel tank with running hot water for at least five minutes. Pour the water out of the fuel sender assembly opening (Rock the tank in order to ensure that the removal of the water from the tank is complete).
  12. Notice: Do not attempt to straighten any kinked nylon fuel lines. Replace any kinked nylon fuel feed or return pipes in order to prevent damage to the vehicle.

  13. Remove the engine compartment fuel feed and return lines.
  14. Caution: Wear safety glasses when using compressed air in order to prevent eye injury.

  15. Use compressed air in order to apply air pressure to the fuel lines in the opposite direction from the normal fuel flow.

Installation Procedure

Notice: If necessary, remove rust or burrs from the fuel pipes with an emery cloth. Use a radial motion with the fuel pipe end in order to prevent damage to the O-ring sealing surface. Use a clean shop towel in order to wipe off the male tube ends. Inspect all the connections for dirt and burrs. Clean or replace the components and assemblies as required.

Reassemble the fuel system as follows:

    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.

  1. Apply a few drops of clean engine oil to the male tube ends of the fuel feed and return engine lines.
  2. Install the engine compartment fuel feed and return lines onto the fuel rail.
  3. Install the fuel sender assembly.
  4. Install the fuel filter. Refer to In-Line Fuel Filter Replacement .
  5. Install the fuel tank. Refer to Fuel Tank and Evaporation Emission Canister Replacement in this section.
  6. Crank the engine for a few seconds. Turn off the engine if the engine starts.
  7. Check for any fuel leaks.