GM Service Manual Online
For 1990-2009 cars only

Fuel Hose/Pipe Replacement - Filter to High Pressure Regulator Passenger/cargo

Tools Required

J 45878 Combustible Gas Detector

Removal Procedure

    Caution: Natural gas is highly flammable. In order to reduce the risk of fire and personal injury, keep sparks, flames, and smoking materials away from the vehicle while you perform the Compressed Natural Gas (CNG) fuel system service.

    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. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical in the G/H Van service manual.
  3. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information in the G/H Van service manual.

  4. Object Number: 924828  Size: SH
  5. Disconnect the fuel line fitting (3) at the filter (1) and discard the copper sealing washer.
  6. Disconnect the fuel line fitting (2) at the high pressure regulator (HPR) and discard the copper sealing washer.
  7. Remove the fuel line from the vehicle.

Installation Procedure

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 924828  Size: SH
  1. Connect the CNG fuel line fitting (3) to the filter (1) using a NEW copper sealing washer.
  2. Tighten
    Tighten the fuel line fitting to 37 N·m (27 lb ft).

  3. Connect the CNG fuel line fitting (2) to the HPR using a NEW copper sealing washer.
  4. Tighten
    Tighten the fuel line fitting to 37 N·m (27 lb ft).

  5. Install the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical in the G/H Van service manual.
  6. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector.

Fuel Hose/Pipe Replacement - Filter to High Pressure Regulator Cutaway

Tools Required

J 45878 Combustible Gas Detector

Removal Procedure

    Caution: Natural gas is highly flammable. In order to reduce the risk of fire and personal injury, keep sparks, flames, and smoking materials away from the vehicle while you perform the Compressed Natural Gas (CNG) fuel system service.

    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. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical in the G/H Van service manual.
  3. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information in the G/H Van service manual.

  4. Object Number: 924836  Size: SH
  5. Disconnect the fuel line fitting (6) at the filter and discard the copper sealing washer.
  6. Disconnect the fuel line fitting (3) at the high pressure regulator (HPR) and discard the copper sealing washer.
  7. Remove the fuel line from the vehicle.

Installation Procedure

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 924836  Size: SH
  1. Connect the CNG fuel line fitting (6) to the filter using a NEW copper sealing washer.
  2. Tighten
    Tighten the fuel line fitting to 37 N·m (27 lb ft).

  3. Connect the CNG fuel line fitting (3) to the HPR using a NEW copper sealing washer.
  4. Tighten
    Tighten the fuel line fitting to 37 N·m (27 lb ft).

  5. Install the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical in the G/H Van service manual.
  6. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector.