1. Relieve the CNG fuel system pressure. Refer to Fuel Pressure Relief .

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.

2. Disconnect the negative battery cable.
3. Remove the AF module assembly. Refer to Alternative Fuel Module Assembly Replacement .
4. Remove the fuel injector. Refer to Fuel Injector Replacement in the Engine Controls section of the J Platform gasoline Service Manual.

Tools Required

J 41416 Ultrasonic Leak Detector

1. Install the fuel injector. Refer to Fuel Injector Replacement in the Engine Controls section of the J Platform gasoline Service Manual.
2. Install the AF module assembly. Refer to Alternative Fuel Module Assembly Replacement .
3. Connect the negative battery cable.

Tighten
Tighten the bolt to 15 N·m (11 lb ft).

4. Start the engine. Inspect for CNG fuel leaks at each serviced fitting using the J 41416 Ultrasonic Leak Detector.