High Pressure Lock-Off Solenoid: Installation
WARNING: This page is about a different car, the 2003 GMC Sierra and 2003 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
WARNING:
Caution The High Pressure Lock-Off (HPL) solenoid seal is more likely to leak at a lower fuel pressure. Always perform the fuel leak procedure exactly as specified. Failure to follow the proper procedures may result in serious injury or damage to the vehicle or part.
- Install a NEW "O" ring on HPL solenoid. Lubricate "O" ring with petroleum jelly before installation. Install the HPL solenoid in the tank and tighten hand-tight. On Pickups, install the CNG fuel tank to the vehicle. See FUEL TANK under FUEL SYSTEMS.
- For all vehicles, tighten the HPL solenoid to specification. See TORQUE SPECIFICATIONS . Ensure that the HPL manual shut-off valve is open by turning the Allen screw valve counter-clockwise until fully seated.
- Fuel the vehicle and check for CNG fuel leaks in 3 stages at the following pressures: 500 psi, 1500 psi and 3000 psi. Using Combustible Gas Detector, inspect for fuel leaks at the HPL solenoid at each pressure. Connect the negative battery cable(s). Tighten cable bolt(s) to specification.
- Prime the CNG fuel system by cycling the ignition ON and OFF several times. Start and operate the engine on CNG. Inspect for fuel leaks at each serviced fitting using Combustible Gas Detector.
- Install the fuel tank cover. See FUEL TANK COVER . Install the truck body or side panel as required on ZW9 equipped vehicles.