GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1996 🢒 Regal 🢒 Engine 🢒 Engine Controls - 3.8L 🢒 Fuel Tank Leak Check

Notice: 

   • Before attempting the Fuel Tank Leak Check, place a dry chemical (Class B) fire extinguisher near work area.
   • Before removing the fuel tank for a suspected leak, make sure the fuel pipes are not leaking onto the fuel tank. Once the fuel tank is removed, make sure fuel is not leaking around the fuel sender assembly O-ring.
   • This check requires a fuel sender assembly and an O-ring to be installed in the fuel tank.

  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief W 3800, Fuel Pressure Relief W 3100, Fuel Pressure Relief W 3.4L.
  2. Drain the fuel tank. Refer to Fuel Tank Draining Procedure W 3800, Fuel Tank Draining W 3100, Fuel Tank Draining Procedure W 3.4L.
  3. Remove the fuel tank. Refer to Fuel Tank Replacement W 3800, Fuel Tank Replacement W 3100, Fuel Tank Replacement W 3.4L.
  4. Cap the fuel feed pipe, the fuel return pipe, and the EVAP pipe on the fuel sender assembly.
  5. Plug the fuel tank filler pipe opening.
  6. Connect a piece of hose to the fuel tank EVAP pipe.
  7. Submerge the fuel tank in water or apply a soap solution to the outside of the fuel tank.

    8. Apply 7 to 10 kPa (1 to 1.5 psi) air pressure to the piece of hose on the fuel tank EVAP pipe.

    Air bubbles appearing from the fuel tank indicate a leak. Replace the fuel tank if it is leaking. Refer to Fuel Tank Replacement W 3800, Fuel Tank Replacement W 3100, Fuel Tank Replacement W 3.4L.