GM Service Manual Online
For 1990-2009 cars only

Caution: Place a dry chemical (Class B) fire extinguisher near the area before performing a Fuel Tank Leak Check. Before removing the fuel tank for a suspected leak, make sure that the fuel pipes or the tubes are not leaking onto the tank. Once removed, make sure that the fuel is not leaking around the fuel sender O-ring. Failure to follow these precautions may result in personal injury.

  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  2. Remove the fuel tank. Refer to Fuel Tank Replacement .
  3. Plug all of the outlets as follows:
  4. • Plug the fuel filler neck and the EVAP pipe outlets.
    • Install the fuel tank sender with the O-ring seal.
    • Plug the fuel return and feed lines.
    • Install a short piece of fuel line on the fuel tank vapor vent tube located on top of the fuel sender.
  5. Apply approximately 7 to 10 kPa (1 to 1.5 psi) of air pressure to the fuel tank through the vapor vent tube. Then, pinch the fuel line in order to retain the pressure.
  6. Test the suspect area for leaks with a soap solution or by submersion. If you detect a leak , replace the tank. Refer to Fuel Tank Replacement .