GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1998 🢒 Corvette 🢒 Engine 🢒 Engine Controls - 5.7L 🢒 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.

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

  1. Disconnect the negative battery cable.
  2. Relieve the fuel system pressure. Refer to the Fuel Pressure Relief .
  3. Drain the fuel tanks. Refer to Fuel Tank Draining .
  4. Remove the fuel tanks.

    5. Refer to Fuel Tank Replacement .

  5. Cap or plug the following on the left fuel tank:
    6. • The 3 fuel sender assembly pipes.
    • The EVAP hose.
    • The fuel tank vent hose.
  6. Cap or plug the following on the right fuel tank:
    7. • The 2 fuel sender assembly pipes.
    • The EVAP hose.

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  7. Install the crossover hose to both fuel tanks.

    8. Tighten
    Tighten the crossover hose clamps to 4 N·m (35 lb in).

    Notice: Do not submerge the fuel tank assembly in water in order to check for leaks in the fuel tank. Submerging the fuel tank in water may damage the electrical components mounted on the fuel tank.

  8. Apply a soap solution to the outside of the fuel tanks.
  9. Apply 10 kPa (1 psi) to the fuel fill hose on the left fuel tank. Air bubbles appearing from the fuel tank(s) indicate a leak.
  10. Replace the fuel tanks if it is leaking.

    11. Refer to Fuel Tank Replacement .