GM Service Manual Online
For 1990-2009 cars only

Fuel Tank Leak Check Pickup

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.

Important: This check requires a fuel sender assembly, a fuel sender gasket, a fuel filler pipe and hose assembly, and a fuel filler cap to be installed in the fuel tank.

    Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  1. Disconnect the negative battery cable.
  2. Relieve the fuel system pressure. Refer to the Fuel Pressure Relief .
  3. Drain the fuel tank. Refer to Fuel Tank Draining .
  4. Remove the fuel tank. Refer to Fuel Tank Replacement .
  5. Remove the fuel feed, return and EVAP pipes from the fuel sender and the fuel tank.
  6. Install the fuel filler cap.
  7. Cap the fuel feed pipe and the fuel return pipe on the fuel sender assembly.
  8. Connect a piece of hose to the EVAP pipe on the fuel sender assembly.
  9. Apply a soap solution to the outside of the fuel tank.
  10. Apply 7-10 kPa (1-1.5 psi) air pressure to the piece of hose on the fuel tank vent pipe. Air bubbles appearing from the fuel tank indicate a leak.
  11. Replace the fuel tank if it is leaking. Refer to Fuel Tank Replacement .

Fuel Tank Leak Check Utility with Single Side Tank

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.

Important: This check requires a fuel sender assembly and a fuel sender gasket to be installed in the fuel tank.

    Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  1. Disconnect the negative battery cable.
  2. Relieve the fuel system pressure. Refer to the Fuel Pressure Relief Procedure .
  3. Drain the fuel tank. Refer to Fuel Tank Draining .
  4. Remove the fuel tank. Refer to Fuel Tank Replacement .
  5. Remove the fuel feed pipe and the return pipe from the fuel sender and the fuel tank.
  6. Cap the fuel feed pipe and the fuel return pipe on the fuel sender assembly.
  7. Cap the fuel fill hose.
  8. Apply a soap solution to the outside of the fuel tank.
  9. Apply 7-10 kPa (1-1.5 psi) air pressure to the fuel tank vent hose. Air bubbles appearing from the fuel tank indicate a leak.
  10. Replace the fuel tank if it is leaking. Refer to Fuel Tank Replacement .

Fuel Tank Leak Check Utility with Dual Tanks - Front Tank

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.

Important: This check requires a fuel sender assembly and a fuel sender gasket to be installed in the fuel tank.

    Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  1. Disconnect the negative battery cable.
  2. Relieve the fuel system pressure. Refer to the Fuel Pressure Relief Procedure .
  3. Drain the fuel tank. Refer to Fuel Tank Draining .
  4. Remove the fuel tank. Refer to Fuel Tank Replacement .
  5. Remove the fuel feed and return pipes from the fuel sender and the fuel tank.
  6. Install the fuel filler cap.
  7. Cap the fuel pipes on the fuel sender assembly.
  8. Cap the fuel fill pipe nipple on the fuel tank.
  9. Connect a piece of hose to the vent pipe nipple on the fuel tank.
  10. Apply a soap solution to the outside of the fuel tank.
  11. Apply 7-10 kPa (1-1½ psi) air pressure to the piece of hose on the fuel tank vent pipe nipple. Air bubbles appearing from the fuel tank indicate a leak.
  12. Replace the fuel tank if it is leaking. Refer to Fuel Tank Replacement .

Fuel Tank Leak Check Utility with Dual Tanks - Rear Tank

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.

Important: This check requires a fuel sender assembly, a fuel sender gasket, a fuel filler pipe and hose assembly, and a fuel filler cap to be installed in the fuel tank.

    Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  1. Disconnect the negative battery cable.
  2. Relieve the fuel system pressure. Refer to the Fuel Pressure Relief Procedure .
  3. Drain the fuel tank. Refer to Fuel Tank Draining .
  4. Remove the fuel tank. Refer to Fuel Tank Replacement .
  5. Install the fuel filler cap.
  6. Cap the EVAP pipes on the fuel tank.
  7. Cap the fuel pipe on the fuel sender.
  8. Cap the rear tank to front tank fuel fill hose nipple on the fuel tank.
  9. Apply a soap solution to the outside of the fuel tank.
  10. Apply 7-10 kPa (1-1.5 psi) air pressure to the vent pipe on the fuel fill pipe assembly. Air bubbles appearing from the fuel tank indicate a leak.
  11. Replace the fuel tank if it is leaking. Refer to Fuel Tank Replacement .