GM Service Manual Online
For 1990-2009 cars only

Fuel Tank Leak Check

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 fuel system pressure. Refer to Fuel Pressure Relief .
  2. Remove fuel tank. Refer to Fuel Tank Replacement .
  3. Plug all outlets as follows:
  4.  - Install filler neck and vent hoses, upper neck assembly and install filler cap.
     - Install fuel tank sender with seal and plug fuel lines.
     - Install a short piece of fuel line on fuel tank meter vent tube.
  5. Apply air pressure to tank through vent tube. When air can be heard escaping from filler neck cap. Approximately 7 to 10 kPa (1 to 1.5 psi), pinch the fuel line hose to retain pressure.
  6. Test suspect area for leaks with soap solution or by submersion. If leak is noted, replace tank. Refer to Fuel Tank Replacement .