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For 1990-2009 cars only

Fuel Hose/Pipes Assembly Replacement P32 Pipes

Removal Procedure

Notice: 

   • Do not attempt to straighten kinked nylon pipes. Replace any kinked nylon pipes in order to prevent damage to the vehicle.
   • Do not attempt to repair sections of nylon pipes. Replace damaged nylon pipes.
   • Replace the vapor pipes with original equipment or parts that meet GM specifications.
   • Replace the vapor hoses with original equipment or parts meeting GM specifications. Use only reinforced fuel-resistant hose identified with the word Fluoroelastomer or GM 6163M on the hose.

    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.

  1. Disconnect the negative battery cable.
  2. Relieve the fuel system pressure. Refer to Fuel Pressure Relief Procedure .

  3. Object Number: 439285  Size: SH
  4. Disconnect the fittings (1) at the engine compartment fuel feed and return pipes.
  5. Disconnect the fuel pipe attaching hardware (2) and (3) from the transmission.

  6. Object Number: 439292  Size: SH
  7. Disconnect the fuel feed and return pipe quick connect fittings (1) near the frame cross member and the transmission tail shaft.

  8. Object Number: 439306  Size: SH
  9. Disconnect the fuel feed and return pipe nuts (1) at the fuel filter and the return pipe union.

  10. Object Number: 439301  Size: SH
  11. Support the fuel tank and lower it to allow access t the fuel lines. Refer to Fuel Tank Replacement (P32) and Fuel Tank Replacement (P42) .
  12. Disconnect the fuel feed and vapor hoses (1) and (2) from the fuel sender assembly. Refer to Quick Connect Fitting(s) Service (Metal Collar) or Quick Connect Fitting(s) Service (Plastic Collar) .
  13. Remove the fuel tank. Refer to Fuel Tank Replacement (P32) and Fuel Tank Replacement (P42) .
  14. Remove the hardware retaining section of pipe to be replaced. Note location of attaching hardware for installation.
  15. Remove the section of pipe and hoses.
  16. Remove rust or burrs from the engine compartment fuel pipes by the following procedure:
  17. 12.1. Use emery cloth in a radial motion with the fuel pipe end in order to prevent damage to the O-ring sealing surface.
    12.2. Using a clean shop towel, wipe off the male tube ends.
    12.3. Inspect all the connectors for dirt and burrs. Clean or replace the components/assemblies as required.

Installation Procedure


    Object Number: 439285  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  1. Connect the fuel feed and return pipes to the engine fuel pipes (1).
  2. Tighten
    Fuel pipe attaching nuts to 27 N·m (20 lb ft) using a back-up wrench.

  3. Position new fuel pipe harness in original location and fuel pipe harness attaching hardware (3) and (4). Reconnect attaching hardware to the transmission housing.

  4. Object Number: 439292  Size: SH
  5. Reconnect the fuel feed and fuel return quick disconnect fittings (1) near the frame cross member and the transmission tail shaft.

  6. Object Number: 439306  Size: SH
  7. Connect the fuel feed pipes (1) to the fuel filter and the return pipe union.

  8. Object Number: 439301  Size: SH
  9. Connect the quick-connect fittings for the fuel and vapor pipes at the fuel sender assembly (1) and (2). Refer to Quick Connect Fitting(s) Service (Metal Collar) or Quick Connect Fitting(s) Service (Plastic Collar) .
  10. Install the fuel tank and attaching hardware if the tank was removed. Refer to Fuel Tank Replacement (P32) .
  11. Tighten the fuel filler cap.
  12. Connect the negative battery cable.
  13. Check for fuel leaks.
  14. 9.1. Turn the ignition switch to the ON position for 2 seconds.
    9.2. Turn the ignition switch to the OFF position for 10 seconds.
    9.3. Again, turn the ignition switch to the ON position.
    9.4. Check for fuel leaks.

Fuel Hose/Pipes Assembly Replacement P42 Pipes

Removal Procedure

Notice: 

   • Do not attempt to straighten kinked nylon pipes. Replace any kinked nylon pipes in order to prevent damage to the vehicle.
   • Do not attempt to repair sections of nylon pipes. Replace damaged nylon pipes.
   • Replace the vapor pipes with original equipment or parts that meet GM specifications.
   • Replace the vapor hoses with original equipment or parts meeting GM specifications. Use only reinforced fuel-resistant hose identified with the word Fluoroelastomer or GM 6163M on the hose.

    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.

  1. Disconnect the negative battery calble.
  2. Relieve the fuel system pressure. Refer to Fuel Pressure Relief Procedure .

  3. Object Number: 439303  Size: SH
  4. Disconnect the fittings (1) at the engine compartment fuel feed and return pipes.
  5. Disconnect the fuel pipe attaching hardware (3) from the transmission housing.
  6. Remove the fuel tank. Refer to Fuel Tank Replacement (P32) or Fuel Tank Replacement (P42) .

  7. Object Number: 439292  Size: SH
  8. Disconnect the fuel feed and return pipe quick connect fittings (1) near the frame cross member and the transmission tail shaft.

  9. Object Number: 439306  Size: SH
  10. Disconnect the fuel feed and return pipe nuts (1) at the fuel filter and the return pipe union.

  11. Object Number: 439301  Size: SH
  12. Support the fuel tank and lower it to allow access to the fuel lines. Refer to Fuel Tank Replacement (P32) and Fuel Tank Replacement (P42) .
  13. Disconnect the fuel feed and vapor hoses (1) and (2) from the fuel sender assembly. Refer to Quick Connect Fitting(s) Service (Metal Collar) or Quick Connect Fitting(s) Service (Plastic Collar) .
  14. Remove the fuel tank. Refer to Fuel Tank Replacement (P32) and Fuel Tank Replacement (P42) .
  15. Remove the hardware retaining section of pipe to be replaced. Note location of attaching hardware for installation.
  16. Remove the section of pipe and hoses.
  17. Remove rust or burrs from the engine compartment fuel pipes by the following procedure:
  18. 13.1. Use emery cloth in a radial motion with the fuel pipe end in order to prevent damage to the O-ring sealing surface.
    13.2. Using a clean shop towel, wipe off the male tube ends.
    13.3. Inspect all the connectors for dirt and burrs. Clean or replace the components/assemblies as required.

Installation Procedure


    Object Number: 439303  Size: SH
  1. Connect the fuel feed and return pipes to the engine fuel pipes (1).
  2. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  3. Connect the fuel pipe attaching hardware (3).
  4. Tighten
    Fuel pipe attaching nuts to 27 N·m (20 lb ft) using a back-up wrench.

  5. Position new fuel pipe harness in original location and fuel pipe harness attaching hardware (3).
  6. Remove protective caps from one end of both fuel pipes.
  7. Leave caps on other end of pipes to prevent dirt from entering.

  8. Apply a few drops of clean engine oil to the male connector tube ends.

  9. Object Number: 439292  Size: SH
  10. Reconnect the fuel feed and fuel return quick discoonect fittings (1) near the frame cross member and the transmission tail shaft.

  11. Object Number: 439306  Size: SH
  12. Connect the fuel feed pipe (1) to the fuel filter and the return pipe union .

  13. Object Number: 439301  Size: SH
  14. Connect the quick-connect fittings for the fuel and vapor pipes at the fuel sender assembly (1) and (2). Refer to Quick Connect Fitting(s) Service (Metal Collar) or Quick Connect Fitting(s) Service (Plastic Collar) .
  15. Install the fuel tank and attaching hardware if the tank was removed. Refer to Fuel Tank Replacement (P32) .
  16. Tighten the fuel filler cap.
  17. Connect the negative battery cable.
  18. Check for fuel leaks.
  19. 12.1. Turn the ignition switch to the ON position for 2 seconds.
    12.2. Turn the ignition switch to the OFF position for 10 seconds.
    12.3. Again, turn the ignition switch to the ON position.
    12.4. Check for fuel leaks.

Fuel Hose/Pipes Assembly Replacement Repair

Steel fuel lines - These are welded steel tubes, meeting GM specifications 124-M, or its equivalent. The fuel feed line is 3/8 inches diameter and the fuel return line is 5/16 inches diameter. Do not use copper or aluminum tubing to replace steel tubing. Those materials do not have satisfactory durability to withstand normal vehicle vibration.

Coupled hose - Do not repair the hoses. Replace them only as an assembly.

Uncoupled hose - Use only reinforced fuel resistant hose, made of Fluoroelastomer material. Do not use a hose within 4 inches (100 mm) of any part of the exhaust system, or within 10 inches (2154 mm) of the catalytic converter. The hoses inside diameter must match the outside diameter of the steel tubing.

Clamps - These are stainless steel, screw bank-type clamps, #2494772, or equivalent.

Steel Fuel Line Repair

  1. Cut a piece of fuel hose 4 inches (100 mm) longer than the section of line to be removed. If you remove more than 6 inches (152 mm), use a combination of steel pipe and hose. The hose length should not be more than 10 inches total.
  2. With a tube cutter, cut a section of the pipe to replace. Use the reamer to form a bead on the ends of the pipe and also on the new section of pipe if used.
  3. Slide the hose clamps onto the pipe and push the hose 2 inches (51 mm) onto each portion of the fuel pipe. Tighten a clamp on each side of the repair.
  4. Secure fuel line to the frame.
  5. Check for leaks.