GM Service Manual Online
For 1990-2009 cars only

Evaporative Emission Hose/Pipe Replacement - Chassis Pickup

Removal Procedure

Important: Clean the fuel and evaporative emission (EVAP) connections and surrounding areas prior to disconnecting the lines in order to avoid possible system contamination.


    Object Number: 1238585  Size: SH
  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  2. Disconnect the fuel feed line (1) at the engine. Refer to Metal Collar Quick Connect Fitting Service .
  3. Disconnect the EVAP canister purge tube line (2).
  4. Cap the fuel rail in order to avoid possible system contamination.
  5. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle .

  6. Object Number: 1238747  Size: SH
  7. Remove the fuel pipe bracket nut.
  8. Remove the fuel pipe bracket from the bellhousing stud.

  9. Object Number: 1549617  Size: SH
  10. Remove the fuel line clips from the brackets on the transmission.
  11. If equipped with 4-wheel drive (4WD), remove the fuel line clip from the bracket on the transfer case.

  12. Object Number: 1238591  Size: SH
  13. Disconnect the fuel and EVAP quick connect fittings. Refer to Plastic Collar Quick Connect Fitting Service .
  14. Cap the fuel and EVAP lines at the fuel tank in order to avoid possible system contamination.

  15. Object Number: 1228114  Size: SH
  16. Remove the fuel and EVAP bundle nuts.
  17. Remove the fuel and EVAP bundle.

Installation Procedure

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1228114  Size: SH
  1. Install the fuel and EVAP bundle.
  2. Install the fuel and EVAP bundle nuts.
  3. Tighten
    Tighten the nuts to 12 N·m (106 lb in).


    Object Number: 1238591  Size: SH
  4. Remove the caps from the fuel and EVAP lines at the fuel tank.
  5. Connect the fuel and EVAP quick connect fittings. Refer to Plastic Collar Quick Connect Fitting Service .

  6. Object Number: 1549617  Size: SH
  7. If equipped with 4WD, install the fuel line clip to the bracket on the transfer case.
  8. Install the fuel line clip(s) to the bracket(s) on the transmission.

  9. Object Number: 1238747  Size: SH
  10. Install the fuel pipe bracket to the bellhousing stud.
  11. Install the fuel pipe bracket nut.
  12. Tighten
    Tighten the nut to 10 N·m (89 lb in).


    Object Number: 1238585  Size: SH
  13. Lower the vehicle.
  14. Remove the cap from the fuel rail.
  15. Connect the fuel feed line (1) at the engine. Refer to Metal Collar Quick Connect Fitting Service .
  16. Connect the EVAP canister purge tube line (2).
  17. Install the fuel fill cap.
  18. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .
  19. Use the following procedure in order to inspect for leaks:
  20. 15.1. Turn the ignition ON, with the engine OFF, for 2 seconds.
    15.2. Turn the ignition OFF for 10 seconds.
    15.3. Turn the ignition ON, with the engine OFF.
    15.4. Inspect for fuel leaks.

Evaporative Emission Hose/Pipe Replacement - Chassis Cab/Chassis

Removal Procedure

Important: Clean the fuel and evaporative emission (EVAP) connections and surrounding areas prior to disconnecting the lines in order to avoid possible system contamination.


    Object Number: 1228187  Size: SH
  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  2. Disconnect the fuel feed and pressure balance lines from the front tank. Refer to Metal Collar Quick Connect Fitting Service .
  3. Cap the fuel and balance lines at the fuel tank in order to avoid possible system contamination.

  4. Object Number: 1228189  Size: SH
  5. Disconnect the fuel feed and pressure balance lines from the rear tank. Refer to Metal Collar Quick Connect Fitting Service .
  6. Cap the fuel and balance lines at the fuel tank in order to avoid possible system contamination.

  7. Object Number: 1228198  Size: SH
  8. Remove the rear fuel line bundle clip nuts.
  9. Remove the rear fuel line bundle.

Installation Procedure


    Object Number: 1228198  Size: SH
  1. Install the rear fuel line bundle.
  2. Install the rear fuel line bundle clip nuts.

  3. Object Number: 1228189  Size: SH
  4. Remove the caps from the fuel and balance lines at the fuel tank.
  5. Connect the fuel feed and pressure balance lines from the rear tank. Refer to Metal Collar Quick Connect Fitting Service .

  6. Object Number: 1228187  Size: SH
  7. Remove the caps from the fuel and balance lines at the fuel tank.
  8. Connect the fuel feed and pressure balance lines from the front tank. Refer to Metal Collar Quick Connect Fitting Service .
  9. Install the fuel fill cap.
  10. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .
  11. Perform the following procedure in order to inspect for leaks.
  12. 9.1. Turn the ignition ON, with the engine OFF, for 2 seconds.
    9.2. Turn the ignition OFF for 10 seconds.
    9.3. Turn the ignition ON, with the engine OFF.
    9.4. Inspect for fuel leaks.

Evaporative Emission Hose/Pipe Replacement - Chassis 1500 Crew Cab

Removal Procedure

Important: Clean the fuel and evaporative emission (EVAP) connections and surrounding areas prior to disconnecting the fittings in order to avoid possible system contamination.


    Object Number: 1238585  Size: SH
  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  2. Disconnect the fuel feed line (1) fitting at the engine. Refer to Metal Collar Quick Connect Fitting Service .
  3. Disconnect the EVAP canister purge tube (2) fitting. Refer to Plastic Collar Quick Connect Fitting Service .
  4. Cap the fuel rail and EVAP lines in order to avoid possible system contamination.
  5. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .

  6. Object Number: 1238747  Size: SH
  7. Remove the fuel pipe bracket nut.
  8. Remove the fuel pipe bracket from the bellhousing stud.
  9. Remove the heated oxygen (HO2S) sensor connector from the bracket.

  10. Object Number: 1549620  Size: SH
  11. Remove the fuel line clips from the brackets on the transmission.
  12. Remove the fuel line clip from the bracket on the transfer case, if equipped with 4 wheel drive (4WD).
  13. Remove the clip from the bracket on the frame.
  14. Remove the transfer case harness from the clip bracket.

  15. Object Number: 924296  Size: SH

    Important: The area around the electro-hydraulic control unit (EHCU) MUST be free from loose dirt to prevent contamination of disassembled anti-lock brake (ABS) components.

  16. Thoroughly wash all contaminants from around the EHCU.
  17. Disconnect the chassis electrical harness connectors from the electronic brake control module (EBCM).

  18. Object Number: 379478  Size: SH
  19. Disconnect the brake lines from the brake pressure modulator valve (BPMV).
  20. Remove the bolts (4) attaching the EHCU bracket to the frame (5).
  21. Remove the EHCU (1).

  22. Object Number: 1223779  Size: SH
  23. Remove the torsion bar bracket, if equipped with 4WD. Refer to Torsion Bar Replacement .
  24. Remove the EVAP canister. Refer to Evaporative Emission Canister Replacement .
  25. Disconnect the fuel line at the tank. Refer to Plastic Collar Quick Connect Fitting Service .
  26. Cap the fuel and EVAP lines in order to avoid possible system contamination.
  27. Remove the fuel/EVAP bundle clip nuts.
  28. Remove the fuel/EVAP bundle.

Installation Procedure

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1223779  Size: SH
  1. Install the fuel/EVAP bundle.
  2. Install the fuel/EVAP bundle clip nuts.
  3. Tighten
    Tighten the nuts to 12 N·m (106 lb in).

  4. Remove the caps from the fuel and EVAP lines.
  5. Connect the fuel line at the tank. Refer to Plastic Collar Quick Connect Fitting Service .
  6. Install the EVAP canister. Refer to Evaporative Emission Canister Replacement .
  7. Install the torsion bar bracket, if equipped with 4WD. Refer to Torsion Bar Replacement .

  8. Object Number: 379478  Size: SH
  9. Install the EHCU (1).
  10. Install the bolts (4) attaching the EHCU bracket to the frame (5).
  11. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).

  12. Connect the brake lines to the BPMV.
  13. Tighten
    Tighten the fittings to 25 N·m (18 lb ft).


    Object Number: 924296  Size: SH
  14. Connect the chassis electrical harness connectors to the EBCM.

  15. Object Number: 1549620  Size: SH
  16. Install the transfer case harness to the clip bracket.
  17. Install the clip to the bracket on the frame.
  18. Install the fuel line clip to the bracket on the transfer case, if equipped with 4WD.
  19. Install the fuel line clips to the brackets on the transmission.

  20. Object Number: 1238747  Size: SH
  21. Install the HO2S sensor connector to the bracket.
  22. Install the fuel pipe bracket to the bellhousing stud.
  23. Install the fuel pipe bracket nut.
  24. Tighten
    Tighten the nut to 10 N·m (89 lb in).

  25. Lower the vehicle.

  26. Object Number: 1238585  Size: SH
  27. Remove the caps from the fuel rail and EVAP lines.
  28. Connect the EVAP canister purge tube (2) fitting. Refer to Plastic Collar Quick Connect Fitting Service .
  29. Connect the fuel feed line (1) fitting at the engine. Refer to Metal Collar Quick Connect Fitting Service .
  30. Install the fuel fill cap.
  31. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .
  32. Use the following procedure in order to inspect for leaks:
  33. 24.1. Turn the ignition ON, with the engine OFF, for 2 seconds.
    24.2. Turn the ignition OFF for 10 seconds.
    24.3. Turn the ignition ON, with the engine OFF.
    24.4. Inspect for fuel leaks.