Tools Required

J 45878 Combustible Gas Detector

Caution: The Compressed Natural Gas (CNG) system operates at pressures up to 24820 kpa (3600 psi). Relieve the CNG fuel system pressure before servicing CNG fuel system components in order to reduce the risk of fire and personal injury.

1. Relieve the CNG fuel system pressure. Refer to Fuel Pressure Relief .
2. Remove the CNG fuel rail. Refer to Fuel Injection Fuel Rail Assembly Replacement .



3. Remove the injector retaining clip (5).
4. Disconnect the injector connector.
5. Remove the CNG fuel injector (6) with a twisting and pulling motion.
6. Ensure the upper O-ring (7) does not remain in the fuel rail.
7. Repeat steps 3-6 for the remaining injectors as necessary.

1. Install the injector to the fuel rail (4) using new upper (7) and lower O-rings (6). Lubricate the O-rings with petroleum jelly or the equivalent.
2. Install the injector retaining clip (3) through the slots in the fuel rail. Ensure the clip is fully seated against the rail.
3. Connect the fuel injector connector.
4. Repeat steps 1-3 for the remaining injectors as necessary.
5. Install the CNG fuel rail. Refer to Fuel Injection Fuel Rail Assembly Replacement .
6. Start the engine. Inspect for CNG fuel leaks at each serviced fitting using the J 45878 .