GM Service Manual Online
For 1990-2009 cars only

Fuel Feed and Fuel Return Lines Rear

Removal Procedure

  1. Remove the fuel tank. Refer to Fuel Tank and Evaporation Emission Canister Replacement .

  2. Object Number: 658376  Size: SH

    Notice: Do not attempt to straighten any kinked nylon fuel lines. Replace any kinked nylon fuel feed or return pipes in order to prevent damage to the vehicle.

  3. Disconnect the fuel feed and return lines (1,5) from the fuel sending unit and discard the clamps.

Installation Procedure

Caution: In order to reduce the risk of fire and personal injury observe the following items:

   • Replace all nylon fuel pipes that are nicked, scratched or damaged during installation, do not attempt to repair the sections of the nylon fuel pipes
   • Do not hammer directly on the fuel harness body clips when installing new fuel pipes. Damage to the nylon pipes may result in a fuel leak.
   • Always cover nylon vapor pipes with a wet towel before using a torch near them. Also, never expose the vehicle to temperatures higher than 115°C (239°F) for more than one hour, or more than 90°C (194°F) for any extended period.
   • Apply a few drops of clean engine oil to the male pipe ends before connecting fuel pipe fittings. This will ensure proper reconnection and prevent a possible fuel leak. (During normal operation, the O-rings located in the female connector will swell and may prevent proper reconnection if not lubricated.)

  1. Clean any contamination from the male line ends of the fuel sending unit.

  2. Object Number: 658376  Size: SH
  3. Connect the fuel feed and return lines to the fuel sending unit with new clamps.
  4. Install the fuel tank. Refer to Fuel Tank and Evaporation Emission Canister Replacement .

Fuel Feed and Fuel Return Lines Center

Removal Procedure

Caution: Gasoline or gasoline vapors are highly flammable. A fire could occur if an ignition source is present. Never drain or store gasoline or diesel fuel in an open container, due to the possibility of fire or explosion. Have a dry chemical (Class B) fire extinguisher nearby.

  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .

  2. Object Number: 721468  Size: SH
  3. Remove the muffler and heat shield. Refer to Exhaust Pipe and Muffler Heat Shields Replacement in Engine Exhaust.
  4. Remove the plastic shield over the fuel lines (the underbody center section).
  5. Remove the attaching hardware that retains the fuel feed and return lines.

  6. Object Number: 721479  Size: SH
  7. Disconnect the quick connect fittings to the center section lines, on the right side almost in line with the catalytic converter. Refer to Servicing Quick Connect Fittings .

  8. Object Number: 721457  Size: SH
  9. Disconnect the fuel feed line from the quick connect fitting at the fuel filter (1). Refer to Servicing Quick Connect Fittings .
  10. Disconnect the fuel return line from the quick connect fitting above the fuel filter (1). Refer to Servicing Quick Connect Fittings .
  11. Remove the fuel feed and return lines.

Installation Procedure

    Caution: In order to reduce the risk of fire and personal injury observe the following items:

       • Replace all nylon fuel pipes that are nicked, scratched or damaged during installation, do not attempt to repair the sections of the nylon fuel pipes
       • Do not hammer directly on the fuel harness body clips when installing new fuel pipes. Damage to the nylon pipes may result in a fuel leak.
       • Always cover nylon vapor pipes with a wet towel before using a torch near them. Also, never expose the vehicle to temperatures higher than 115°C (239°F) for more than one hour, or more than 90°C (194°F) for any extended period.
       • Apply a few drops of clean engine oil to the male pipe ends before connecting fuel pipe fittings. This will ensure proper reconnection and prevent a possible fuel leak. (During normal operation, the O-rings located in the female connector will swell and may prevent proper reconnection if not lubricated.)

  1. Clean any of the contamination from the male line ends and apply a few drops of clean engine oil.
  2. Install the fuel feed and return lines.

  3. Object Number: 721457  Size: SH
  4. Connect the fuel feed line at the quick connect fitting at the fuel filter. Refer to Servicing Quick Connect Fittings .
  5. Connect the fuel return line at the quick connect fitting above the fuel filter. Refer to Servicing Quick Connect Fittings .

  6. Object Number: 721479  Size: SH
  7. Connect the quick connect fittings to the center section lines, on the right side almost in line with the catalytic converter. Refer to Servicing Quick Connect Fittings .
  8. Install attaching hardware on the fuel feed and return lines.

  9. Object Number: 721468  Size: SH
  10. Install the heat shield and muffler. Refer to Exhaust Pipe and Muffler Heat Shields Replacement in Engine Exhaust.
  11. Tighten the fuel filler cap.
  12. Connect the negative battery cable.
  13. Crank the engine for a few seconds. Turn OFF the engine if the engine starts.
  14. Check for any fuel leaks.
  15. Install the underbody plastic shield over the fuel lines if no leaks are present.

Fuel Feed and Fuel Return Lines Engine Compartment

Removal Procedure

Caution: Gasoline or gasoline vapors are highly flammable. A fire could occur if an ignition source is present. Never drain or store gasoline or diesel fuel in an open container, due to the possibility of fire or explosion. Have a dry chemical (Class B) fire extinguisher nearby.

  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  2. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  3. Remove the plastic shield over the lines (the underbody center section).

  4. Object Number: 721464  Size: SH
  5. Remove the front fuel feed and return lines from the attaching hardware.

  6. Object Number: 721479  Size: SH
  7. Disconnect the quick connect fittings to the center section lines, on the right side almost in line with the catalytic converter. Refer to Servicing Quick Connect Fittings .
  8. Pull the fuel feed-return lines through the underbody frame support.
  9. Lower the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  10. Disconnect the fuel lines from the fuel rail.

  11. Object Number: 721464  Size: SH
  12. Pull the fuel lines through the fender well and out of the engine compartment.

Installation Procedure

    Caution: In order to reduce the risk of fire and personal injury observe the following items:

       • Replace all nylon fuel pipes that are nicked, scratched or damaged during installation, do not attempt to repair the sections of the nylon fuel pipes
       • Do not hammer directly on the fuel harness body clips when installing new fuel pipes. Damage to the nylon pipes may result in a fuel leak.
       • Always cover nylon vapor pipes with a wet towel before using a torch near them. Also, never expose the vehicle to temperatures higher than 115°C (239°F) for more than one hour, or more than 90°C (194°F) for any extended period.
       • Apply a few drops of clean engine oil to the male pipe ends before connecting fuel pipe fittings. This will ensure proper reconnection and prevent a possible fuel leak. (During normal operation, the O-rings located in the female connector will swell and may prevent proper reconnection if not lubricated.)

  1. Remove the protective caps from the replacement lines.

  2. Object Number: 721464  Size: SH

    Important: Wherever the lines pass through the metal, be sure that the grommets, where used, are installed and in good condition.

  3. Install the fuel lines through the fender well from the engine compartment.
  4. Clean the contamination, if any, from the male line ends and apply a few drops of clean engine oil.
  5. Reconnect the fuel lines to the fuel rail.
  6. Tighten
    Tighten the feed and return lines to 15 N·m (11 lb ft).

  7. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  8. Important: Wherever the lines pass through the metal, be sure that the grommets, where used, are installed and in good condition.

  9. Feed the lines through the underbody frame support.

  10. Object Number: 721479  Size: SH
  11. Reconnect the quick connect fittings to the center section lines, on the right side almost in line with catalytic converter. Refer to Servicing Quick Connect Fittings .
  12. Install the fuel feed and return line retaining hardware.
  13. Lower the vehicle.
  14. Tighten the fuel filler cap.
  15. Connect the negative battery cable.
  16. Crank the engine for a few seconds. Turn OFF the engine if the engine starts.
  17. Check for any fuel leaks.
  18. Install the underbody plastic shield over the lines if no leaks are present.