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. This check requires the fuel sender and o-ring to be installed.
  2. Disconnect battery cables.
  3. Drain the fuel tank (go to Fuel Tank Draining .
  4. Remove fuel tank (go to Fuel Tank Replacement .
  5. Cap fuel feed tube and fuel return tube on fuel sender.
  6. Connect a piece of hose to the filler tube nipple and plug opposite end.
  7. Submerge tank in water or apply soap solution to outside of tank.
  8. Apply 35 kPa (5 psi) air pressure to the vent hose of the fuel tank (a leak will show up as bubbles).