GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2008 🢒 Express 🢒 Engine 🢒 Engine Controls and Fuel - 4.3L 🢒 Fuel System Cleaning

    Caution: Refer to Battery Disconnect Caution in the Preface section.

  1. Disconnect the negative battery cable.
  2. Relieve fuel system pressure. Refer to Fuel Pressure Relief .
  3. Drain fuel tank. Refer to Fuel Tank Draining .
  4. Remove the fuel tank. Refer to Fuel Tank Replacement .
  5. Remove the fuel tank fuel pump module. Refer to Fuel Tank Fuel Pump Module Replacement .
  6. Inspect the fuel strainer. Replace a contaminated strainer and inspect the fuel pump.
  7. Inspect the fuel pump inlet for dirt and debris. Replace the fuel pump if you find dirt or debris in the fuel pump inlet.

    8. Important: 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.

  8. Flush the fuel tank with hot water.
  9. Pour the water out of the fuel sender assembly opening.
  10. Rock the tank to ensure that removal of the water from the tank is complete.
  11. Inspect the fuel filter for contamination.
  12. Replace the fuel filter if the filter is plugged.

    13. Important: Only use oil-free compressed air to blow out the fuel pipes.

  13. Clean the fuel lines by applying air pressure in the opposite direction of the fuel flow.
  14. Install the fuel tank fuel pump module with a new seal into the fuel tank. Refer to Fuel Tank Fuel Pump Module Replacement .
  15. Install the fuel tank. Refer to Fuel Tank Replacement .
  16. Inspect for leaks:
    17. 16.1. Turn ON the ignition for 2 seconds.
    16.2. Turn OFF the ignition for 10 seconds.
    16.3. Turn ON the ignition .
    16.4. Inspect for fuel leaks.