GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Chevy Suburban - 2WD 🢒 Engine 🢒 Engine Controls - 7.4L 🢒 Fuel Tank Leak Check

Fuel Tank Leak Test

If fuel is leaking from the fuel tank, the tank should be replaced. Make sure that the fuel lines are not leaking onto the fuel tank. Never attempt to repair a leaking 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 pressure. Refer to Fuel Pressure Relief Procedure .
  3. Drain the fuel tank. Refer to Fuel Tank Draining Procedure Draining Fuel Tank .
  4. Remove the fuel tank.
    5. • Refer to Fuel Tank Replacement (Suburban) Fuel Tank (Suburban)Fuel Tank (Suburban) for the Suburban.
    • Refer to Fuel Tank Replacement (Tahoe/Yukon) Fuel Tank (Tahoe/Yukon)Fuel Tank (Tahoe/Yukon) for the Yukon/Tahoe.
    • Refer to Fuel Tank Replacement (Pick-up - Side Tank) Fuel Tank (Pick-up - Side Tank)Fuel Tank (Pick-up - Side Tank) for the Pick-up.
    • Refer to Fuel Tank Replacement (Extended Cab - Side Tank) Fuel Tank (Extended Cab - Side Tank)Fuel Tank (Extended Cab - Side Tank) for the Extended Cab.
    • Refer to Fuel Tank Replacement (Cab and Chassis - Side Tank) Fuel Tank (Cab and Chassis - Side Tank)Fuel Tank (Cab and Chassis - Side Tank) for the Cab and Chassis with a side tank.
    • Refer to Fuel Tank Replacement (Cab and Chassis - Rear Tank) Fuel Tank (Cab and Chassis - Rear Tank)Fuel Tank (Cab and Chassis - Rear Tank) for the Cab and Chassis with a rear tank only.
    • Refer to Fuel Tank Replacement (4 Door Utility) Fuel Tank ReplacementFuel Tank Replacement for the 4DR Utility.
  5. Plug all of the fuel tank outlets.
  6. Apply 7-10 kPa (1-1.5 psi) air pressure through the vent tube.
  7. Test for leaks with a soap solution or by submersion.
  8. Replace the fuel tank if a leak is found.