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Home >> Chevrolet >> 2004 >> Chevy Express G2500, Van Cargo Extended, 4.3 X, 4L60E/M30 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - 4.3L (Introduction) >> Repair Instructions >> Fuel System Cleaning
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Fuel System Cleaning

    CAUTION: Refer to Battery Disconnect Caution in Cautions and Notices.
  1. Disconnect the negative battery cable.
  2. Relieve fuel system pressure. Refer to Fuel Pressure Relief Procedure .
  3. Drain fuel tank. Refer to Fuel Tank Draining Procedure .
  4. Remove the fuel tank. Refer to Fuel Tank Replacement (Cutaway Van Side Tank)  or Fuel Tank Replacement (Passenger/Cargo Van)  or Fuel Tank Replacement (Cutaway Van Rear Tank) .
  5. Remove the fuel sender assembly. Refer to Fuel Sender Assembly 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.
  9. Flush the fuel tank with hot water.
  10. Pour the water out of the fuel sender assembly opening.
  11. Rock the tank to ensure that removal of the water from the tank is complete.
  12. Inspect the fuel filter for contamination.
  13. Replace the fuel filter if the filter is plugged. Refer to Fuel Filter Replacement (Passenger/Cargo Van)  or Fuel Filter Replacement (Cutaway Van) .
  14. IMPORTANT: Only use oil-free compressed air to blow out the fuel pipes.
  15. Clean the fuel lines by applying air pressure in the opposite direction of the fuel flow.
  16. Install the fuel sender assembly with a new seal into the fuel tank. Refer to Fuel Sender Assembly Replacement .
  17. Install the fuel tank. Refer to Fuel Tank Replacement (Cutaway Van Side Tank)  or Fuel Tank Replacement (Passenger/Cargo Van)  or Fuel Tank Replacement (Cutaway Van Rear Tank) .
  18. Inspect for leaks:
    1. Turn ON the ignition for 2 seconds.
    2. Turn OFF the ignition for 10 seconds.
    3. Turn ON the ignition.
    4. Inspect for fuel leaks.