GM Service Manual Online
For 1990-2009 cars only

Important: Before you attempt the Fuel Tank Leak Check, place a dry chemical (Class B) fire extinguisher near the work area.

  1. Install the J 41415-40 fill tank cap adaptor.
  2. Connect the J 41413 EVAP pressure/purge diagnostic station to the fill tank cap adaptor.
  3. With a scan tool, seal the evaporative emissions (EVAP) system.
  4. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  5. With the EVAP diagnostic station, maintain 15 in. H2O (3.75 kPa) within the fuel tank.
  6. Important: You may need to partially lower the fuel tank in order to inspect the top of the fuel tank and fuel sender assembly O-ring. Refer to Fuel Tank Replacement .

  7. With the J 41416 ultrasonic leak detector, test for leaks in the fuel tank and in the EVAP pipes.
  8. Inspect for fuel leaking from the fuel tank.
  9. If you find a leak, refer to the following component replacement procedures:
  10. • For a fuel tank leak, refer to Fuel Tank Replacement .
    • For a fuel sender O-ring or fuel sender leak, refer to Fuel Sender Assembly Replacement .
    • For a fuel or EVAP pipe leak, refer to Fuel Hoses/Pipes Replacement - Filter to Tank .