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Engine Control System - 6.0L - Alternative Fuel (Introductions): Removal & Installation GMC Savana G2500

Testing & Diagnostics ~9189 words

Removal Procedure

  1. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  2. Remove the fender brace mounting bolts (3).
  3. Remove the fender brace.
  4. Remove the FICM hold-down screws (7) from the mounting bracket.
  5. Remove the connector position assurance lock and disconnect the electrical connector (2) from the FICM.
  6. Remove the FICM. If the FICM mounting bracket does not have to be removed proceed to Step 3 of the Installation Procedure.
  7. Remove the FICM mounting bracket bolts (1).
  8. Remove the FICM mounting bracket nut (4) from the horn mounting stud.
  9. Remove the FICM mounting bracket from the vehicle.

Installation Procedure

  1. Install the FICM mounting bracket onto the horn mounting stud. Tighten: Tighten the nut to 9 N.m (7 lb ft).
  2. Install the FICM mounting bracket bolts (1). Tighten: Tighten the bolts to 12 N.m (9 lb ft).
  3. Loosely install all of the FICM hold-down screws (7). Tighten: Tighten the screws to 12 N.m (9 lb ft).
  4. Connect the electrical connector (2) to the FICM and install the connector position assurance lock.
  5. Install the fender brace and bolts (3). Tighten: Tighten the bolts to 12 N.m (9 lb ft).
  6. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  1. Remove the weight distributing hitch if equipped. Refer to Weight Distribution Hitch Replacement in Frame and Underbody in the G/H Van Service Manual.
  2. Remove the tank shield bolts while an assistant holds the shield in place.
  3. Lower the shield from the vehicle.
  1. Position the shield around the tank frame.
  2. While an assistant holds the shield in place, loosely install the shield retaining bolts. Tighten: Tighten the bolts to 24 N.m (18 lb ft).
  3. Install the weight distributing hitch if equipped. Refer to Weight Distribution Hitch Replacement in Frame and Underbody in the G/H Van Service Manual.
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  3. Raise and properly support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information in the G/H Van Service Manual.
  4. Remove the fuel tank cover. Refer to «Fuel Tank Cover Replacement»(ref-185854-S01404073892005082900000) .
  5. Disconnect the fuel outlet line (2) from the high pressure lock-off (HPL) solenoid.
  6. Disconnect the electrical connector (3) at the high pressure lock-off solenoid.
  7. Attach the J 45397-2 to a transmission jack. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  8. Support the tank assembly with the J 45397-2 and transmission jack. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  9. Remove the tank assembly retaining bolts (5,7).
  10. Rotate the tank straps (4,6) away from the tank.
  11. Lower the tank (1) from the vehicle with the transmission jack.
  12. Lift the tank from the J 45397-2 using the J 45529 and a suitable overhead lifting device. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  13. Vent the CNG fuel from the CNG fuel tank if necessary. Refer to «Fuel Tank Venting Procedure»(ref-185854-S17889565712005082900000) .
  1. Position the tank assembly beneath the vehicle.
  2. Raise the tank assembly onto the tank frame mounts.
  3. Rotate the tank straps (4,6) against the tank.
  4. Install the mounting bolts (5,7). Tighten: Tighten the mounting bolts to 39 N.m (29 lb ft).
  5. Connect the fuel outlet line (2) to the high pressure lock-off using a new O-ring. Lubricate the O-ring with petroleum jelly or equivalent. Tighten: Tighten the fitting to 37 N.m (27 lb ft).
  6. Connect the electrical connector (3) at the high pressure lock-off solenoid.
  7. Connect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  8. Prime the CNG fuel system by cycling the ignition ON and OFF several times.
  9. Start the engine and use the J 45878 in order to inspect for CNG fuel system leaks at each serviced fitting. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  10. Install the fuel tank cover. Refer to «Fuel Tank Cover Replacement»(ref-185854-S01404073892005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  3. Raise and properly support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information in the G/H Van Service Manual.
  4. Remove the fuel tank cover. Refer to «Fuel Tank Cover Replacement»(ref-185854-S01404073892005082900000) .
  5. Disconnect the fuel outlet line (4) from the high pressure lock-off (HPL) solenoid.
  6. Disconnect the electrical connectors (1,2,4) at the high pressure lock-off solenoids.
  7. Attach the J 45397 (2) to a transmission jack (3). See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  8. Support the tank assembly (1) with the J 45397 and transmission jack. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  9. Remove the exhaust tailpipe from the hanger.
  10. Remove all of the tank assembly retaining nuts (2).
  11. Lower the tank assembly from the vehicle with the transmission jack.
  1. Position the tank assembly beneath the vehicle.
  2. Raise the tank assembly onto the tank frame studs.
  3. Install the mounting nuts. Tighten: Tighten the mounting nuts to 85 N.m (63 lb ft).
  4. Connect the fuel outlet line (4) to the high pressure lock-off using a new O-ring. Lubricate the O-ring with petroleum jelly or equivalent. Tighten: Tighten the fitting to 37 N.m (27 lb ft).
  5. Connect the electrical connectors (1,2,4) at the high pressure lock-off solenoids.
  6. Connect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  7. Prime the CNG fuel system by cycling the ignition ON and OFF several times.
  8. Start the engine and use the J 45878 in order to inspect for CNG fuel system leaks at each serviced fitting. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  9. Install the fuel tank cover. Refer to «Fuel Tank Cover Replacement»(ref-185854-S01404073892005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  3. Raise and properly support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information in the G/H Van Service Manual.
  4. Remove the fuel tank cover. Refer to «Fuel Tank Cover Replacement»(ref-185854-S01404073892005082900000) .
  5. Disconnect the electrical connectors (1-4) at the high pressure lock-off solenoids.
  6. Disconnect the fuel outlet line (2) from the high pressure lock-off (HPL) solenoid.
  7. Attach the J 45397 (2) to a transmission jack (3). See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  8. Support the tank assembly (1) with the J 45397 and transmission jack. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  9. Remove the tank assembly retaining nuts (1) and bolts (2).
  10. Lower the tank assembly from the vehicle with the transmission jack.
  1. Position the tank assembly beneath the vehicle.
  2. Raise the tank assembly onto the tank frame studs.
  3. Install the mounting nuts (1) and bolts (2). Tighten: Tighten the mounting nuts to 81 N.m (60 lb ft).
  4. Connect the fuel outlet line (4) to the high pressure lock-off (2) using new O-rings. Lubricate the O-rings with petroleum jelly or equivalent. Tighten: Tighten the fitting to 37 N.m (27 lb ft).
  5. Connect the electrical connectors (1-4) at the high pressure lock-off solenoids as necessary.
  6. Connect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G Van Service Manual.
  7. Prime the CNG fuel system by cycling the ignition ON and OFF several times.
  8. Start the engine and use the J 45878 in order to inspect for CNG fuel system leaks at each serviced fitting. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  9. Install the fuel tank cover. Refer to «Fuel Tank Cover Replacement»(ref-185854-S01404073892005082900000) .
  1. Remove the screws (3) that retain the fuel filler door to the body.
  2. Remove the fuel filler door from the body.
  1. Position the fuel filler door to the body.
  2. Install the fuel filler door retaining screws (3) to the body. Tighten: Tighten the screws to 5 N.m (44 lb in).
  1. Remove the screws (3) and spacers (2) that retain the fuel filler door to the body.
  2. Remove the fuel filler door from the body.
  1. Position the fuel filler door to the body.
  2. Install the fuel filler door retaining screws (3) and spacers (2) to the body. Tighten: Tighten the screws to 5 N.m (44 lb in).
  1. Relieve the CNG fuel system pressure. Refer to the «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  3. Remove the fill line fitting (3) from the fill valve.
  4. Remove the fill valve jam nut (1).
  5. Remove the fill valve (7) from the mounting plate.
  1. Install the fill valve (7) into the mounting plate.
  2. Install the fill valve jam nut (1). Tighten: Tighten the nut to 28 N.m (21 lb ft).
  3. Install the fill line fitting (3) to the fill valve using a new O-ring. Lubricate the O-ring with petroleum jelly or equivalent before installation. Tighten: Tighten the fill line fitting to 37 N.m (27 lb ft).
  4. Connect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  5. Prime the CNG fuel system by cycling the ignition ON and OFF several times.
  6. Start the engine and use the J 45878 in order to inspect for CNG fuel system leaks at each serviced fitting. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to the «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  3. Remove the fill line fitting (3) from the fill valve.
  4. Remove the fill valve jam nut (5).
  5. Remove the fill valve (7) from the mounting plate (6).
  1. Install the fill valve (7) into the mounting plate (6).
  2. Install the fill valve jam nut (5). Tighten: Tighten the nut to 28 N.m (21 lb ft).
  3. Install the fill line fitting (3) to the fill valve using a new O-ring. Lubricate the O-ring with petroleum jelly or equivalent before installation. Tighten: Tighten the fill line fitting to 37 N.m (27 lb ft).
  4. Connect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  5. Prime the CNG fuel system by cycling the ignition ON and OFF several times.
  6. Start the engine and use the J 45878 in order to inspect for CNG fuel system leaks at each serviced fitting. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  1. Remove the O-ring (1).
  2. Remove the circlip (2).
  3. Remove the fill valve filter (3).
  4. Clean the filter in solvent.
  5. Blow dry the filter using compressed air.
  6. Be sure that the filter passages are clear. Replace the filter if needed.
  1. Install the fill valve filter (3).
  2. Install the circlip (2).
  3. Install the O-ring (1).
  1. Relieve the CNG fuel system pressure. Refer to the «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  3. Remove the outlet line (2) from the filter.
  4. Discard the copper sealing washer.
  5. Remove the inlet line from the filter.
  6. Discard the copper sealing washer.
  7. Remove the filter hold down clamp bolt.
  8. Remove the filter.
  1. Install the filter into the hold down clamp. Tighten: Tighten the clamp bolt to 13 N.m (115 lb in).
  2. Install the fuel outlet line fitting (2) to the filter with a NEW copper sealing washer. Tighten: Tighten the line fitting to 37 N.m (27 lb ft).
  3. Install the fuel inlet line fitting to the filter with a NEW copper sealing washer. Tighten: Tighten the line fitting to 37 N.m (27 lb ft).
  4. Connect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  5. Prime the CNG fuel system by cycling the ignition ON and OFF several times.
  6. Start the engine and use the J 45878 in order to inspect for CNG fuel system leaks at each serviced fitting. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to the «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  3. Remove the outlet line (3) from the filter.
  4. Discard the copper sealing washer.
  5. Remove the inlet line from the filter.
  6. Discard the copper sealing washer.
  7. Remove the filter hold down clamp bolt.
  8. Remove the filter.
  1. Install the filter into the hold down clamp. Tighten: Tighten the clamp bolt to 13 N.m (115 lb in).
  2. Install the fuel outlet line fitting (3) to the filter with a NEW copper sealing washer. Tighten: Tighten the line fitting to 37 N.m (27 lb ft).
  3. Install the fuel inlet line fitting to the filter with a NEW copper sealing washer. Tighten: Tighten the line fitting to 37 N.m (27 lb ft).
  4. Connect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  5. Prime the CNG fuel system by cycling the ignition ON and OFF several times.
  6. Start the engine and use the J 45878 in order to inspect for CNG fuel system leaks at each serviced fitting. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to the «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  3. Remove the CNG fuel tank cover. Refer to «Fuel Tank Cover Replacement»(ref-185854-S01404073892005082900000) .
  4. Disconnect the fuel tank pressure (FTP) sensor (2) electrical connector.
  5. Remove the FTP sensor (2) from the tank valve. Discard the O-ring.
  1. Install the FTP sensor (2) in the tank valve using a new O-ring. Tighten: Tighten the FTP sensor to 15 N.m (133 lb in).
  2. Connect the FTP sensor electrical connector.
  3. Connect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  4. Start the vehicle and use the J 45878 in order to inspect for CNG fuel leaks at each serviced fitting. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  5. Install the CNG fuel tank cover. Refer to «Fuel Tank Cover Replacement»(ref-185854-S01404073892005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to the «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  3. Clamp off the coolant hoses using coolant hose pinch pliers.
  4. Mark the hoses prior to removal.
  5. Remove the hose clamps and hoses from the high pressure regulator coolant fittings (1, 2).
  6. Remove the fuel inlet lines (1,4) from the high pressure regulator (3) and discard the O-rings.
  7. Remove the fuel outlet line (2) from the filter and discard the copper sealing washer.
  8. Remove the mounting bracket bolts (1).
  9. Remove the high pressure regulator assembly.
  1. Install the high pressure regulator and mounting bracket (2) to the vehicle frame using the mounting bolts (1). Tighten: Tighten the bolts to 38 N.m (28 lb ft).
  2. Install the fuel inlet fitting (3) using a new O-ring. Lubricate the O-ring with petroleum jelly or equivalent. Tighten: Tighten the fuel inlet fitting to 45 N.m (33 lb ft).
  3. Connect the fuel inlet line (1,4) to the fuel inlet fitting using new O-rings. Lubricate the O-ring with petroleum jelly or equivalent. Tighten: Tighten the fuel inlet line fittings to 45 N.m (33 lb ft).
  4. Connect the fuel outlet line (2) to the filter using a new copper sealing washer. Tighten: Tighten the fuel outlet line fitting to 37 N.m (27 lb ft).
  5. Install the coolant hoses and clamps to the high pressure regulator coolant fittings (1, 2) as marked during removal.
  6. Remove the coolant hose pinch pliers.
  7. Connect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  8. Prime the CNG fuel system by cycling the ignition ON and OFF several times.
  9. Start the engine and use the J 45878 in order to inspect for CNG fuel system leaks at each serviced fitting. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  10. Inspect for proper coolant level and fill as necessary.
  1. Relieve the CNG fuel system pressure. Refer to the «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  3. Clamp off the coolant hoses using coolant hose pinch pliers.
  4. Mark the hoses prior to removal.
  5. Remove the hose clamps and hoses from the high pressure regulator coolant fittings (1, 2).
  6. Remove the fuel inlet lines (1,4) from the high pressure regulator (2) and discard the O-rings.
  7. Remove the fuel outlet line (3) from the filter and discard the copper sealing washer.
  8. Remove the mounting bracket bolts (1).
  9. Remove the mounting bracket nut (3).
  10. Remove the high pressure regulator assembly (2).
  1. Install the high pressure regulator and mounting bracket (2) to the vehicle frame using the mounting bolts (1). Tighten: Tighten the bolts to 38 N.m (28 lb ft).
  2. Install the high pressure regulator mounting support bracket nut (3). Tighten: Tighten the nut to 38 N.m (28 lb ft).
  3. Install the fuel inlet fitting (3) using a new O-ring. Lubricate the O-ring with petroleum jelly or equivalent. Tighten: Tighten the fuel inlet fitting to 45 N.m (33 lb ft).
  4. Connect the fuel inlet line (1,4) to the fuel inlet fitting using new O-rings. Lubricate the O-ring with petroleum jelly or equivalent. Tighten: Tighten the fuel inlet line fittings to 45 N.m (33 lb ft).
  5. Connect the fuel outlet line (3) to the filter using a new copper sealing washer. Tighten: Tighten the fuel outlet line fitting to 37 N.m (27 lb ft).
  6. Install the coolant hoses and clamps to the high pressure regulator coolant fittings (1, 2) as marked during removal.
  7. Remove the coolant hose pinch pliers.
  8. Connect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  9. Prime the CNG fuel system by cycling the ignition ON and OFF several times.
  10. Start the engine and use the J 45878 in order to inspect for CNG fuel system leaks at each serviced fitting. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  11. Inspect for proper coolant level and fill as necessary.
  1. Relieve the CNG fuel system pressure. Refer to the «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  3. Remove the fuel line (4) from the fuel inlet fitting (3).
  4. Remove the fuel inlet fitting (3) from the high pressure regulator (2).
  5. Remove the fuel filter spring, seal and filter (1).
  1. Install the filter spring, filter and seal in order (1).
  2. Install the fuel inlet fitting (3) using a new O-ring. Lubricate the O-ring with petroleum jelly or equivalent. Tighten: Tighten the fuel inlet fitting to 45 N.m (33 lb ft).
  3. Install the fuel inlet line (4) to the fuel inlet fitting (3) using a new O-ring. Lubricate the O-ring with petroleum jelly or equivalent. Tighten: Tighten the fuel inlet line fitting to 37 N.m (27 lb ft).
  4. Connect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  5. Prime the CNG fuel system by cycling the ignition ON and OFF several times.
  6. Start the engine and use the J 45878 in order to inspect for CNG fuel system leaks at each serviced fitting. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  1. Remove the fuel tank cover. Refer to «Fuel Tank Cover Replacement»(ref-185854-S01404073892005082900000) .
  2. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  3. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Platform Service Manual.
  4. Remove the CNG fuel tank from the vehicle. Refer to «Fuel Tank Replacement - Rear (Passenger/Cargo)»(ref-185854-S24799367272005082900000) or «Fuel Tank Replacement - Rear (Cutaway)»(ref-185854-S08299222712005082900000) .
  5. Vent the CNG fuel pressure from the tank. Refer to «Fuel Tank Venting Procedure»(ref-185854-S17889565712005082900000) .
  6. Disconnect the vent hose (1) from the HPL.
  7. Remove the manual vent tool and all fittings.
  8. Remove the fuel inlet fitting from the HPL and discard the O-rings.
  9. Remove the fuel outlet fitting from the HPL and discard the O-rings.
  10. Using the J 43602 HPL crowfoot removal tool, loosen the HPL. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  11. Unthread the HPL from the CNG fuel tank and discard the O-ring.
  12. Inspect the inside of the CNG fuel tank for water, rust, or other contaminants.
  13. If necessary, clean the CNG fuel tank. Refer to «Fuel Tank Cleaning»(ref-185854-S38952227772005082900000) .
  1. Install a NEW O-ring on the HPL.
  2. Lubricate the O-ring with petroleum jelly.
  3. Install the HPL in the tank and tighten hand-tight.
  4. Tighten the HPL as specified below. Tighten: Tighten the HPL to a nominal torque of 305 N.m (225 lb ft) at 0 degrees. You must compensate for the torque wrench and the HPL crowfoot. Refer to the formula below for compensation of the torque wrench. To obtain your dial reading perform the following procedure: Multiply your torque wrench length in inches by 305 (225). 18 inch torque wrench example: 18 X 305 = 5,490. Add 3 to the length of your torque wrench. 18 inch torque wrench example: 18 + 3 = 21. Divide the first value obtained by the second value obtained. The result indicates the amount of torque your wrench should tighten the HPL to. 18 inch torque wrench example: 5,490 divided by 21 = 261.4. For an 18 inch long torque wrench tighten the HPL to 261.4 N.m.
  5. Complete the fuel tank installation by connecting the fuel lines, electrical connectors and fuel tank pressure sensor. Refer to «Fuel Tank Replacement - Front (KL8)»(ref-185854-S18211563042005082900000) or «Fuel Tank Replacement - Rear (Passenger/Cargo)»(ref-185854-S24799367272005082900000) or «Fuel Tank Replacement - Rear (Cutaway)»(ref-185854-S08299222712005082900000) .
  6. Fuel the vehicle and check for CNG fuel leaks in 3 stages at the following pressures: 500 psi 1,500 psi 3,000 psi
  7. With the J 45878 , inspect for fuel leaks at the HPL at EACH pressure. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  8. Connect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van Service Manual.
  9. Start and operate the engine on CNG.
  10. Inspect for fuel leaks at each serviced fitting with the J 45878 . See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  11. Attach the information label supplied with the replacement HPL in a visible location on the head of the tank.
  12. Install the fuel tank cover. Refer to «Fuel Tank Cover Replacement»(ref-185854-S01404073892005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  3. Before removal, clean the fuel rail assemblies with a spray type engine cleaner, GM X-30A or equivalent, if necessary. Follow the package instructions. Do not soak fuel rails in liquid cleaning solvent.
  4. Remove the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  5. Disconnect the low pressure lock-off (LPL) solenoid electrical connector.
  6. Remove the LPL solenoid coil retaining nut (2).
  7. Remove the LPL solenoid coil (3).
  8. Remove the LPL solenoid core tube (4).
  9. Disconnect the fuel inlet line (8) and discard the copper sealing washer.
  10. Disconnect the fuel crossover line (7) and discard the copper sealing washer.
  11. Remove the LPL solenoid housing mounting screws (1).
  12. Remove the LPL solenoid housing from the fuel rail (5) and discard the O-ring (12).
  1. Install the low pressure lock-off (LPL) solenoid housing to the fuel rail (5) using a new O-ring (12). Lubricate the O-ring with petroleum jelly or equivalent before installation. Tighten: Tighten the mounting screws to 4 N.m (35 lb in).
  2. Connect the CNG fuel inlet line (8) using a NEW copper sealing washer. Tighten: Tighten the fuel line fitting to 37 N.m (27 lb ft).
  3. Connect the CNG fuel crossover line (7) using a NEW copper sealing washer. Tighten: Tighten the fuel line fitting to 27 N.m (20 lb ft).
  4. Ensure the LPL piston assembly (5) spring is installed inside the core tube (4). Lubricate the piston O-ring with petroleum jelly or equivalent before installation.
  5. Install the core tube (4) and piston assembly (5) into the LPL solenoid housing (1). Lubricate the core tube O-ring with petroleum jelly or equivalent before installation. Tighten: Tighten the core tube to 41 N.m (30 lb ft).
  6. Install the LPL solenoid coil (3) onto the core tube (4).
  7. Install the LPL solenoid coil retaining nut (2). Tighten: Tighten the nut to 14 N.m (10 lb ft).
  8. Connect the LPL solenoid electrical connector.
  9. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  10. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or equivalent combustible gas detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  11. Install the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Relieve the gasoline fuel system pressure. Refer to Fuel Pressure Relief Procedure in Engine Controls in the G/H Van service manual.
  3. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  4. Remove the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  5. Before removal, clean the fuel rail assemblies with a spray type engine cleaner, GM X-30A or equivalent, if necessary. Follow the package instructions. Do not soak fuel rails in liquid cleaning solvent.
  6. Disconnect the CNG fuel lines (7, 8, 10) from the fuel rails.
  7. Disconnect the fuel rail temperature and pressure sensor electrical connectors (3, 4).
  8. Disconnect the low pressure lock-off solenoid connector.
  9. Disconnect the 8 CNG fuel injector electrical connectors (2, 12).
  10. Disconnect the accelerator control cable and the cruise control cable from the cable bracket.
  11. Disconnect the cruise control cable engine-end fitting from the stud on the throttle lever, if equipped.
  12. Disconnect the accelerator control cable and the cruise control cable from the throttle body.
  13. Remove the upper engine wire harness retainer nut.
  14. Disconnect the evaporative emission (EVAP) purge valve harness connector.
  15. Reposition the upper engine wire harness aside.
  16. Mark the electrical connectors to their corresponding gasoline injectors to ensure correct sequential injector firing order after reassembly. Pull the connector position assurance (CPA) (2) of the injector connector up.
  17. Pull the tab (1) on the injector connector in.
  18. While pushing the tab (1) on the injector connector in, release the CPA (2).
  19. Disconnect the fuel injector electrical connector.
  20. Repeat steps for each injector connector.
  21. Disconnect the fuel feed and return pipes (1, 2) from the fuel rail.
  22. Disconnect the fuel pressure regulator vacuum line.
  23. Loosen the crossover tube to right fuel rail retainer screw.
  24. Remove the right fuel rail attaching nuts (1).
  25. Remove the left fuel rail attaching nuts (1).
  26. Remove the gasoline and CNG fuel rails as an assembly.
  1. Install the fuel rail assemblies onto the intake manifold.
  2. Apply a 5 mm (0.020 in) band of GM P/N 1234382 threadlock, or equivalent, to the threads of all of the fuel rail attaching studs.
  3. Install the right fuel rail attaching nuts (1). Tighten: Tighten the bolts to 4 N.m (35 lb in).
  4. Install the left fuel rail attaching nuts (1). Tighten: Tighten the nuts to 4 N.m (35 lb in).
  5. Tighten the gasoline crossover pipe retainer screws to 3.8 N.m (34 lb in).
  6. Connect the fuel injector electrical connectors to the corresponding engine cylinder injector for both gasoline and CNG (1, 2, 11, 12).
  7. Connect the CNG fuel rail pressure sensor (4) and temperature sensor (3) electrical connectors.
  8. Connect the low pressure lock-off solenoid electrical connector.
  9. Connect the CNG fuel inlet line (8) using a NEW copper sealing washer. Tighten: Tighten the fuel line fitting to 37 N.m (27 lb ft).
  10. Connect the CNG fuel crossover line (7, 10) using NEW copper sealing washers. Tighten: Tighten the fuel line fittings to 27 N.m (20 lb ft).
  11. Connect the fuel pressure regulator vacuum line.
  12. Connect the gasoline fuel feed and return pipes (1, 2) to the fuel rail.
  13. Position the upper engine wire harness in place.
  14. Connect the EVAP purge solenoid connector.
  15. Install the retainer nut to the upper engine wire harness. Tighten: Tighten the nut to 5.5 N.m (49 lb in).
  16. Connect the accelerator control cable and the cruise control cable to the cable bracket.
  17. Connect the accelerator control cable and the cruise control cable to the throttle body.
  18. Connect the cruise control cable engine-end fitting to the stud on the throttle lever, if equipped.
  19. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  20. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  21. With a scan tool command a switch-over to gasoline and inspect for gasoline fuel leaks.
  22. Install the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  3. Remove the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  4. Before removal, clean the fuel rail assemblies with a spray type engine cleaner, GM X-30A or equivalent, if necessary. Follow the package instructions. Do not soak fuel rails in liquid cleaning solvent.
  5. Disconnect the CNG fuel lines (7, 8, 10) from the fuel rails.
  6. Disconnect the fuel rail temperature and pressure sensor electrical connectors (3, 4).
  7. Disconnect the low pressure lock-off solenoid connector.
  8. Disconnect the 8 CNG fuel injector electrical connectors (2, 12).
  9. Disconnect the accelerator control cable and the cruise control cable from the cable bracket.
  10. Disconnect the cruise control cable engine-end fitting from the stud on the throttle lever, if equipped.
  11. Disconnect the accelerator control cable and the cruise control cable from the throttle body.
  12. Remove the upper engine wire harness retainer nut.
  13. Reposition the upper engine wire harness aside.
  14. Remove the right fuel rail attaching bolts (1).
  15. Remove the CNG fuel rail.
  16. Remove the left fuel rail attaching bolts (1).
  17. Remove the CNG fuel rail.
  1. Install the fuel rail assemblies onto the intake manifold.
  2. Apply a 5 mm (0.020 in) band of GM P/N 1234382 threadlock, or equivalent, to the threads of all of the fuel rail attaching bolts.
  3. Install the right fuel rail attaching bolts (1). Tighten: Tighten the bolts to 4 N.m (35 lb in).
  4. Install the left fuel rail attaching bolts (1). Tighten: Tighten the bolts to 4 N.m (35 lb in).
  5. Connect the fuel injector electrical connectors to the corresponding engine cylinder injector (2, 12).
  6. Connect the CNG fuel rail pressure sensor (4) and temperature sensor (3) electrical connectors.
  7. Connect the low pressure lock-off solenoid electrical connector.
  8. Connect the CNG fuel inlet line (8) using a NEW copper sealing washer. Tighten: Tighten the fuel line fitting to 37 N.m (27 lb ft).
  9. Connect the CNG fuel crossover line (7, 10) using NEW copper sealing washers. Tighten: Tighten the fuel line fittings to 27 N.m (20 lb ft).
  10. Position the upper engine wire harness in place.
  11. Install the retainer nut to the upper engine wire harness. Tighten: Tighten the nut to 5.5 N.m (49 lb in).
  12. Connect the accelerator control cable and the cruise control cable to the cable bracket.
  13. Connect the accelerator control cable and the cruise control cable to the throttle body.
  14. Connect the cruise control cable engine-end fitting to the stud on the throttle lever, if equipped.
  15. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  16. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  17. Install the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  1. Remove the fuel rail assembly. Refer to «Fuel Rail Assembly Replacement (KL6)»(ref-185854-S38493791022005082900000) or «Fuel Rail Assembly Replacement (KL8)»(ref-185854-S41653591922005082900000) .
  2. Remove the injector (7) retainer bolt and clip (10).
  3. Remove the injector from the fuel rail with a pulling a twisting motion.
  4. Repeat steps 2 and 3 for the remaining fuel injectors.
  1. Install the fuel injector (7) into the fuel rail (5) using a new O-ring (6). Lubricate the new O-ring with petroleum jelly.
  2. Install the fuel injector retainer bolt and clip (10). Tighten: Tighten the retainer bolt to 7 N.m (61 lb in).
  3. Lubricate the new injector tip O-ring (8) with clean engine oil.
  4. Repeat steps 1, 2 and 3 for the remaining fuel injectors.
  5. Install the fuel rail assembly. Refer to «Fuel Rail Assembly Replacement (KL6)»(ref-185854-S38493791022005082900000) or «Fuel Rail Assembly Replacement (KL8)»(ref-185854-S41653591922005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  3. Before removal, clean the fuel rail with a spray type engine cleaner, GM X-30A or equivalent, if necessary. Follow the package instructions. Do not soak fuel rails in liquid cleaning solvent.
  4. Remove the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  5. Disconnect the fuel rail pressure (FRP) sensor electrical connectors (4).
  6. Remove the FRP sensor (13) and discard the O-ring.
  1. Install the fuel rail pressure (FRP) sensor (13) using a new O-ring. Lubricate the O-ring with petroleum jelly or equivalent before installation. Tighten: Tighten the FRP sensor to 8 N.m (71 lb in).
  2. Connect the FRP electrical connector (4).
  3. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  4. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  5. Install the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  3. Before removal, clean the fuel rail with a spray type engine cleaner, GM X-30A or equivalent, if necessary. Follow the package instructions. Do not soak fuel rails in liquid cleaning solvent.
  4. Remove the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  5. Disconnect the fuel rail temperature (FRT) sensor electrical connector (3).
  6. Remove the FRT sensor (11) and discard the O-ring.
  1. Install the fuel rail temperature (FRT) sensor (11) using a new O-ring. Lubricate the O-ring with petroleum jelly or equivalent before installation. Tighten: Tighten the FRT sensor to 13 N.m (10 lb ft).
  2. Connect the FRT electrical connector (3).
  3. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  4. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  5. Install the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure 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. Disconnect the fill line fitting (7) at the fill valve and discard the O-ring.
  5. Disconnect the fuel line fitting (10) at the check valve (11) and discard the O-ring.
  6. Remove the P-clamp screw (8).
  7. Remove the fuel line from the vehicle.
  1. Connect the fill line fitting (7) to the fill valve using a NEW O-ring. Lubricate the new O-ring with petroleum jelly or equivalent before installation. Tighten: Tighten the fill line fitting to 45 N.m (33 lb ft).
  2. Connect the fill line fitting (10) to the check valve (11) using a NEW O-ring. Lubricate the new O-ring with petroleum jelly or equivalent before installation. Tighten: Tighten the fuel line fitting to 45 N.m (33 lb ft).
  3. Install the P-clamp mounting screw (8). Tighten: Tighten the mounting screw to 7 N.m (62 lb in).
  4. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  5. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure 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. Disconnect the fill line fitting (1) at the fill valve and discard the O-ring.
  5. Disconnect the fuel line fitting (4) at the check valve (5) and discard the O-ring.
  6. Remove the P-clamp bolt (2).
  7. Remove the fuel line from the vehicle.
  1. Connect the fill line fitting (1) to the fill valve using a NEW O-ring. Lubricate the new O-ring with petroleum jelly or equivalent before installation. Tighten: Tighten the fill line fitting to 45 N.m (33 lb ft).
  2. Connect the fill line fitting (4) to the check valve (5) using a NEW O-ring. Lubricate the new O-ring with petroleum jelly or equivalent before installation. Tighten: Tighten the fuel line fitting to 45 N.m (33 lb ft).
  3. Install the P-clamp mounting bolt (8), washer and nut. Tighten: Tighten the mounting bolt to 25 N.m (18 lb in).
  4. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  5. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  3. Remove the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  4. Disconnect the CNG crossover fuel line (7, 10) from the fuel rails.
  1. Connect the CNG fuel crossover line (7, 10) using NEW copper sealing washers. Tighten: Tighten the fuel line fittings to 27 N.m (20 lb ft).
  2. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  3. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  4. Install the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  3. Remove the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  4. Disconnect the CNG fuel line (8) from the fuel rail.
  5. Remove the fuel line P-clamp mounting bolts (9).
  6. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information in the G/H Van service manual.
  7. Remove the fuel line P-clamp mounting bolt (7).
  8. Disconnect the fuel line fitting (2) at the filter.
  9. Remove the fuel line from the vehicle.
  1. Connect the CNG fuel line fitting (2) to the filter using a NEW copper sealing washer. Tighten: Tighten the fuel line fitting to 37 N.m (27 lb ft).
  2. Install the fuel line P-clamp and mounting bolt (7). Tighten: Tighten the bolt to 10 N.m (89 lb in).
  3. Install the LEFT fuel line P-clamp and mounting bolt (9). Tighten: Tighten the left P-clamp bolt to 34 N.m (25 lb ft)
  4. Install the RIGHT fuel line P-clamp and mounting bolt (9). Tighten: Tighten the right P-clamp bolt to 7 N.m (62 lb in)
  5. Connect the fuel line fitting (8) to the fuel rail. Tighten: Tighten the fuel line fitting to 37 N.m (27 lb ft)
  6. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  7. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  8. Install the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  3. Remove the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  4. Disconnect the CNG fuel line (8) from the fuel rail.
  5. Remove the fuel line P-clamp mounting bolts (9).
  6. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information in the G/H Van service manual.
  7. Remove the fuel line P-clamp mounting bolt (7).
  8. Disconnect the fuel line fitting (3) at the filter.
  9. Remove the fuel line from the vehicle.
  1. Connect the CNG fuel line fitting (3) to the filter using a NEW copper sealing washer. Tighten: Tighten the fuel line fitting to 37 N.m (27 lb ft).
  2. Install the fuel line P-clamp and mounting bolt (7). Tighten: Tighten the bolt to 10 N.m (89 lb in).
  3. Install the LEFT fuel line P-clamp and mounting bolt (9). Tighten: Tighten the left P-clamp bolt to 34 N.m (25 lb ft)
  4. Install the RIGHT fuel line P-clamp and mounting bolt (9). Tighten: Tighten the right P-clamp bolt to 7 N.m (62 lb in)
  5. Connect the fuel line fitting (8) to the fuel rail. Tighten: Tighten the fuel line fitting to 37 N.m (27 lb ft)
  6. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  7. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  8. Install the engine cover. Refer to Engine Cover Replacement in Interior Trim in the G/H Van service manual.
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure 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. Disconnect the fuel line fitting (3) at the filter (1) and discard the copper sealing washer.
  5. Disconnect the fuel line fitting (2) at the high pressure regulator (HPR) and discard the copper sealing washer.
  6. Remove the fuel line from the vehicle.
  1. Connect the CNG fuel line fitting (3) to the filter (1) using a NEW copper sealing washer. Tighten: Tighten the fuel line fitting to 37 N.m (27 lb ft).
  2. Connect the CNG fuel line fitting (2) to the HPR using a NEW copper sealing washer. Tighten: Tighten the fuel line fitting to 37 N.m (27 lb ft).
  3. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  4. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure 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. Disconnect the fuel line fitting (6) at the filter and discard the copper sealing washer.
  5. Disconnect the fuel line fitting (3) at the high pressure regulator (HPR) and discard the copper sealing washer.
  6. Remove the fuel line from the vehicle.
  1. Connect the CNG fuel line fitting (6) to the filter using a NEW copper sealing washer. Tighten: Tighten the fuel line fitting to 37 N.m (27 lb ft).
  2. Connect the CNG fuel line fitting (3) to the HPR using a NEW copper sealing washer. Tighten: Tighten the fuel line fitting to 37 N.m (27 lb ft).
  3. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  4. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure 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. Remove the CNG fuel tank cover. Refer to «Fuel Tank Cover Replacement»(ref-185854-S01404073892005082900000) .
  5. Disconnect the fuel line fitting (2, 3) at each high pressure lock-off (HPL) fitting.
  6. Remove the fuel line from the vehicle.
  1. Connect the CNG fuel line between the high pressure lock-off solenoid fittings (2, 3) using NEW O-rings. Lubricate the new O-rings with petroleum jelly or equivalent before installation. Tighten: Tighten the fuel line fittings to 45 N.m (33 lb ft).
  2. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  3. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  4. Install the CNG fuel tank cover. Refer to «Fuel Tank Cover Replacement»(ref-185854-S01404073892005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure 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. Remove the CNG fuel tank cover. Refer to «Fuel Tank Cover Replacement»(ref-185854-S01404073892005082900000) .
  5. Disconnect the fuel line fitting (3, 4) at each high pressure lock-off (HPL) fitting.
  6. Remove the fuel line from the vehicle.
  1. Connect the CNG fuel line between the high pressure lock-off solenoid fittings (3, 4) using NEW O-rings. Lubricate the new O-rings with petroleum jelly or equivalent before installation. Tighten: Tighten the fuel line fittings to 45 N.m (33 lb ft).
  2. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  3. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  4. Install the CNG fuel tank cover. Refer to «Fuel Tank Cover Replacement»(ref-185854-S01404073892005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure 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. Disconnect the fill line fitting (10) at the check valve (11) and discard the O-ring.
  5. Remove the check valve (11) from the tee fitting (1) and discard the O-ring.
  1. Install the check valve (11) to the tee fitting (1) using a NEW O-ring. Lubricate the new O-ring with petroleum jelly or equivalent before installation. Tighten: Tighten the check valve to 45 N.m (33 lb ft).
  2. Connect the fill line fitting (10) to the check valve (11) using a NEW O-ring. Lubricate the new O-ring with petroleum jelly or equivalent before installation. Tighten: Tighten the fuel line fitting to 45 N.m (33 lb ft).
  3. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  4. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure 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. Disconnect the fuel line fitting (4) at the check valve (5) and discard the O-ring.
  5. Remove the check valve (5) from the tee fitting (7) and discard the O-ring.
  1. Install the check valve (5) to the tee fitting (7) using a NEW O-ring. Lubricate the new O-ring with petroleum jelly or equivalent before installation. Tighten: Tighten the fill line fitting to 45 N.m (33 lb ft).
  2. Connect the fill line fitting (4) to the check valve (5) using a NEW O-ring. Lubricate the new O-ring with petroleum jelly or equivalent before installation. Tighten: Tighten the fuel line fitting to 45 N.m (33 lb ft).
  3. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  4. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure 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. Disconnect the fuel line fitting (2) at the check valve tee (1).
  5. Mark the location and remove the fuel line P-clamp mounting bolts (2, 3, 4) and clamps.
  6. Disconnect the fuel line fitting (4) at the high pressure lock-off (HPL) solenoid.
  7. Remove the fuel line from the vehicle.
  1. Install the fuel line and P-clamps (2, 3, 4) into the vehicle. Tighten: Tighten the mounting bolts to 10 N.m (89 lb in).
  2. Connect the CNG fuel line fitting (2) to the check valve tee (1). Tighten: Tighten the fuel line fitting to 45 N.m (33 lb ft).
  3. Connect the CNG fuel line fitting (4) to the HPL. Tighten: Tighten the fuel line fitting to 45 N.m (33 lb ft).
  4. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  5. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure 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. Disconnect the fuel line fitting (2) at the check valve tee (1).
  5. Disconnect the fuel line fitting (4) at the high pressure lock-off (HPL) solenoid.
  6. Remove the fuel line from the vehicle.
  1. Connect the CNG fuel line fitting (2) to the check valve tee (1). Tighten: Tighten the fuel line fitting to 45 N.m (33 lb ft).
  2. Connect the CNG fuel line fitting (4) to the HPL. Tighten: Tighten the fuel line fitting to 45 N.m (33 lb ft).
  3. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  4. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure 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. Disconnect the CNG fuel line (4) from the high pressure regulator (HPR).
  5. Mark the location and remove the fuel line P-clamp mounting bolts (1, 2, 5, 6) and clamps.
  6. Disconnect the fuel line fitting (4) at the check valve tee (1).
  7. Remove the fuel line from the vehicle.
  1. Install the fuel line and P-clamps (1, 2, 5, 6) into the vehicle. Tighten: Tighten the U-nut mounting bolts to 10 N.m (89 lb in). Tighten the self-tapping mounting bolts to 7 N.m (62 lb in).
  2. Connect the CNG fuel line fitting (4) to the check valve tee. Tighten: Tighten the fuel line fitting to 45 N.m (33 lb ft).
  3. Connect the CNG fuel line fitting (4) to the HPR (3). Tighten: Tighten the fuel line fitting to 45 N.m (33 lb ft).
  4. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  5. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .
  1. Relieve the CNG fuel system pressure. Refer to «Fuel Pressure Relief Procedure»(ref-185854-S02905361662005082900000) .
  2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure 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. Disconnect the CNG fuel line (4) from the high pressure regulator (HPR).
  5. Mark the location and remove the fuel line P-clamp mounting bolts (1, 2, 3, 4) and clamps.
  6. Disconnect the fuel line fitting (4) at the check valve tee (1).
  7. Remove the fuel line from the vehicle.
  1. Install the fuel line and P-clamps (1, 2, 3, 4) into the vehicle. Tighten: Tighten the mounting bolts to 10 N.m (89 lb in).
  2. Connect the CNG fuel line fitting (4) to the check valve tee. Tighten: Tighten the fuel line fitting to 45 N.m (33 lb ft).
  3. Connect the CNG fuel line fitting (4) to the HPR (2). Tighten: Tighten the fuel line fitting to 45 N.m (33 lb ft).
  4. Install the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical in the G/H Van service manual.
  5. Start the vehicle and inspect for CNG fuel leaks at the serviced fittings with the J 45878 or an equivalent leak detector. See «Special Tools and Equipment»(ref-185854-S39958709232005082900000) .

More articles — Engine Control System - 6.0L - Alternative Fuel (Introductions)