GM Service Manual Online
For 1990-2009 cars only

Note: Only use oil free compressed air to blow out the fuel pipes.

  1. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection.
  2. Remove the fuel tank module. Refer to Fuel Tank Fuel Pump Module Replacement.
  3. Inspect the fuel tank module strainer, if equipped. If the strainer is contaminated replace the fuel tank module.
  4. Inspect the fuel tank module inlet for dirt and debris. Replace the fuel tank module if you find dirt or debris in the fuel pump inlet.
  5. Note: When flushing the fuel tank, handle the fuel and water mixture as a hazardous material. Handle the fuel and water mixture in accordance with all applicable local, state, and federal laws and regulations.

  6. Flush the fuel tank with hot water.
  7. Pour the water out of the fuel module opening. Rock the tank to be sure that removal of the water from the tank is complete.
  8. Remove the fuel rail. Refer to Fuel Injection Fuel Rail Assembly Replacement.
  9. Drain the fuel from the fuel rail. It will be necessary to remove the fuel injectors from the fuel rail to properly clear all debris from the fuel rail and fuel injectors. Refer to Fuel Injector Replacement.
  10. Use light shop air to remove any debris from the fuel rail and injectors.
  11. Use light shop air in the opposite direction of the fuel flow in order to remove any debris from the fuel lines. Catch any fuel from the fuel lines with an approved gasoline container.
  12. Install the fuel injectors to the fuel rail. Refer to Fuel Injector Replacement.
  13. Install the fuel rail. Refer to Fuel Injection Fuel Rail Assembly Replacement.
  14. Install the fuel tank module. Refer to Fuel Tank Fuel Pump Module Replacement.
  15. Refill the fuel tank.
  16. Install the fuel fill cap.
  17. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection.
  18. Note: If the fuel pump or sender assembly was not replaced, purge the fuel sender assembly.

  19. Purge the fuel tank module.
  20. 17.1. Disconnect the fuel feed line quick connect fitting from the fuel tank to the chassis line. Refer to Plastic Collar Quick Connect Fitting Service.
    17.2. Connect a length of hose to the fuel feed pipe.
    17.3. Insert the other end of the hose into an empty 3.8 liter (1 gallon) approved gasoline container.
    17.4. Add 23 liters (6 gallons) of clean fuel into the fuel tank.
    17.5. Turn on the fuel pump using the scan tool until 2 liters (1/2 gallon) of fuel flows into the fuel container.
  21. Inspect for leaks.
  22. 18.1. Turn the ignition switch ON for 2 seconds.
    18.2. Turn the ignition switch OFF for 10 seconds.
    18.3. Turn the ignition switch ON.
    18.4. Inspect for fuel leaks.