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For 1990-2009 cars only

Evaporative Emission Hoses/Pipes Replacement - Engine Chassis

Removal Procedure


    Object Number: 329579  Size: SH
  1. Disconnect the engine purge pipe (1) from the chassis purge pipe (2).
  2. Cap the engine purge pipe in order to prevent possible contamination.

  3. Object Number: 329553  Size: SH
  4. Disconnect the chassis fuel and EVAP pipe retainer (1) from the upper front of dash mounting stud (3).

  5. Object Number: 67889  Size: SH
  6. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  7. Remove the exhaust intermediate pipe.

  8. Object Number: 67894  Size: SH
  9. Remove the driveline tunnel closeout panel. Refer to Floor Panel Tunnel Panel Reinforcement Replacement in Propeller Shaft.

  10. Object Number: 329567  Size: SH
  11. Remove the EVAP canister vent valve (2) from the bracket (1).

  12. Object Number: 329558  Size: SH
  13. Disconnect the rear purge pipe (1) at the chassis purge pipe (3).
  14. Cap the rear purge pipe.

  15. Object Number: 329574  Size: SH
  16. Remove the chassis purge pipe (4) rear underbody retainer nuts (3).
  17. Remove the chassis purge pipe (4) from the rear underbody retainers (2).
  18. Disconnect the chassis purge pipe (4) from the side underbody retainers (6).
  19. Remove the chassis purge pipe.

Installation Procedure


    Object Number: 329574  Size: SH

    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.)

    Important: 

       • Follow the same routing as the original pipe.
       • Secure the pipe in order to prevent chafing.
       • Do not kink or bend the pipe.

  1. Install the chassis purge pipe (4) into the side underbody retainers (6).
  2. Install the chassis purge pipe (4) into the rear underbody retainers (2).
  3. Install the underbody retainers (2) on the mounting studs (1).
  4. 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.

  5. Install the chassis purge pipe (4) underbody retainer nuts (3).
  6. Tighten
    Tighten the EVAP pipe retainer bracket nuts to 6 N·m (53 lb in).


    Object Number: 329558  Size: SH
  7. Uncap the rear EVAP pipe.
  8. Connect the rear EVAP pipe (1) to the chassis purge pipe (3).

  9. Object Number: 329567  Size: SH
  10. Install the EVAP canister vent valve (2) to the bracket (1).

  11. Object Number: 67894  Size: SH
  12. Install the driveline tunnel closeout panel. Refer to Floor Panel Tunnel Panel Reinforcement Replacement in Propeller Shaft.

  13. Object Number: 67889  Size: SH
  14. Install the exhaust intermediate pipe.
  15. Lower the vehicle.
  16. Uncap the engine purge pipe.

  17. Object Number: 329553  Size: SH
  18. Connect the chassis fuel and EVAP pipe retainer (1) at the upper front of dash mounting stud (3).
  19. Tighten
    Tighten the fuel and EVAP pipe bracket retainer nut to 6 N·m (53 lb in).


    Object Number: 329579  Size: SH
  20. Connect the engine purge pipe (1) to the chassis purge pipe (2).

Evaporative Emission Hoses/Pipes Replacement - Engine Chassis/Tank

Removal Procedure


    Object Number: 329567  Size: SH
  1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. For vehicles equipped with an automatic transmission, remove the right muffler . Refer to Exhaust Muffler Replacement - Right Side in Engine Exhaust.
  3. Remove the EVAP vent valve (2) from the bracket (1).

  4. Object Number: 329558  Size: SH
  5. Disconnect the rear EVAP purge pipe (1) at the chassis EVAP purge pipe (3).
  6. Cap the chassis EVAP purge pipe.

  7. Object Number: 561137  Size: SH
  8. Remove the right rear wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Rear End.
  9. Remove the EVAP canister access cover.

  10. Object Number: 609762  Size: SH
  11. Disconnect the EVAP purge pipe at the canister.
  12. Remove the rear EVAP purge pipe.

Installation Procedure


    Object Number: 609762  Size: SH

    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. Route the EVAP purge pipe through the right tunnel brace opening.
  2. Connect the EVAP purge pipe to the canister.

  3. Object Number: 329558  Size: SH
  4. Remove the cap from the chassis EVAP purge pipe.
  5. Connect the rear EVAP purge pipe (1) to the chassis EVAP purge pipe (3).

  6. Object Number: 329567  Size: SH
  7. Install the EVAP vent valve (2) to the bracket (1).
  8. For vehicles equipped with automatic transmission, install the right muffler. Refer to Exhaust Muffler Replacement - Right Side in Engine Exhaust.

  9. Object Number: 561137  Size: SH
  10. Install the EVAP canister access cover.
  11. Install the right rear wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Rear End.
  12. Lower the vehicle.

Evaporative Emission Hoses/Pipes Replacement - Engine Tank/Tank

Tool Required

J 34730-1A Fuel Pressure Gauge

Removal Procedure


    Object Number: 561133  Size: SH
  1. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  2. Relieve the fuel system pressure. Refer to the Fuel Pressure Relief .
  3. Drain the fuel tanks below the level of the fuel tank crossover hose. Refer to Fuel Tank Draining .
  4. For vehicles equipped with automatic transmission, remove the left and right muffler. Refer to Exhaust Muffler Replacement - Right Side , and to Exhaust Muffler Replacement - Left Side in Engine Exhaust.
  5. Disconnect the tank crossover hose (5) at the right fuel tank and the left fuel tank.
  6. Disconnect the EVAP pipe (2) at the right tank EVAP pipe (3) and the left tank EVAP pipe (1).
  7. Remove the rear EVAP pipe (2).
  8. Cap the open pipes in order to prevent possible contamination.

Installation Procedure


    Object Number: 561133  Size: SH

    Notice: Replace the EVAP pipes and hoses with the original equipment or parts that meet the GM specifications for those parts. The replacement EVAP pipe must have the same type of fittings as the original pipe in order to ensure the integrity of the connection. When replacing EVAP hoses, use only reinforced fuel-resistant hose identified with the word Fluoroelastomer or GM 6163-M on the hose. The inside hose diameter must match the outside pipe diameter. Do not use rubber hose within 100 mm (4 in) of any part of the exhaust system or within 254 mm (10 in) of the catalytic converter.

  1. Remove the caps from the pipes.
  2. Connect the EVAP pipe (2) at the right tank EVAP pipe (3) and the left tank EVAP pipe (1).
  3. Connect the tank crossover hose (5) at the right fuel tank and the left fuel tank.
  4. Push the clamp (4) outboard against the fuel tank, keeping the clamp parallel with the white stripe on the tank crossover hose.
  5. Tighten
    Tighten the tank crossover hose clamps to 4 N·m (35 lb in).

  6. Install the right and left muffler. Refer to Exhaust Muffler Replacement - Right Side and to Exhaust Muffler Replacement - Left Side in Engine Exhaust.
  7. Refill the fuel system.
  8. Tighten the fuel filler cap.
  9. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical
  10. Use the following procedure in order to inspect for leaks:
  11. 9.1. Turn the ignition switch ON, with the engine OFF for 2 seconds.
    9.2. Turn the ignition switch OFF, for 10 seconds.
    9.3. Turn the ignition switch ON, with the engine OFF.
    9.4. Inspect for fuel leaks.
  12. Program the transmitters. Refer to Transmitter Programming in Keyless Entry.

Evaporative Emission Hoses/Pipes Replacement - Engine Vent

Removal Procedure


    Object Number: 561130  Size: SH
  1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. For vehicles equipped with automatic transmission, remove the right muffler . Refer to Exhaust Muffler Replacement - Right Side in Engine Exhaust.
  3. Disconnect the vent hose (2) from the EVAP vent valve (1).
  4. Remove the clamp from the vent hose.

  5. Object Number: 561137  Size: SH
  6. Remove the right rear wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Rear End.
  7. Remove the EVAP canister access cover.

  8. Object Number: 561128  Size: SH
  9. Disconnect the vent hose from the EVAP canister.
  10. Remove the vent hose.
  11. Cap the EVAP vent valve and the EVAP canister in order to prevent possible EVAP system contamination.

Installation Procedure


    Object Number: 561128  Size: SH

    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 caps from the EVAP vent valve and the EVAP canister.
  2. Route the vent hose over the floor panel tunnel panel rear brace.
  3. Install the clamps on the vent hose.
  4. Connect the vent hose to the EVAP canister.

  5. Object Number: 561130  Size: SH
  6. Connect the vent hose (2) to the EVAP vent valve.
  7. For vehicles equipped with automatic transmission, install the right muffler . Refer to Exhaust Muffler Replacement - Right Side in Engine Exhaust.

  8. Object Number: 561137  Size: SH
  9. Install the EVAP canister access cover.
  10. Install the right rear wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Rear End.
  11. Lower the vehicle.