GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 38185 Spring Hose Clamp Pliers

Removal Procedure


    Object Number: 296265  Size: SH
  1. Remove the battery heat shield. Refer to Battery Heat Shield Replacement in Engine Electrical.
  2. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  3. Remove the intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical.
  4. Using the J 38185 , release and reposition the heater inlet and outlet hose clamps.
  5. Separate the heater hoses from heater pipes.
  6. Disconnect the hose clamp and hose from the RH air injection check valve.

  7. Object Number: 63229  Size: SH
  8. Remove the RH air injection check valve to LH cylinder head bolt.
  9. Remove the RH air injection check valve to RH cylinder head bolts.
  10. Remove the RH air injection pipe.

  11. Object Number: 621745  Size: SH
  12. Remove the nut retaining the heater pipe bracket to the cowl.
  13. Remove the heater pipe to heater core retaining bolt.
  14. Important: Be sure to cap or plug the open heater core to prevent contamination.

  15. Disconnect the heater pipe assembly from the heater core, allow any remaining coolant to drain, discard the seal washers and cap or plug the heater core to prevent contamination.
  16. Remove the heater pipe assembly from the vehicle.

Installation Procedure


    Object Number: 621745  Size: SH
  1. Remove the cap or plug from the heater core.
  2. Using a lint-free clean, dry cloth, carefully clean the sealing surfaces of the heater pipe assembly and the heater core.
  3. Lightly coat the new seal washers with coolant.
  4. Carefully slide the new sealing washers onto the heater pipe assembly until seated.
  5. Install the heater pipe assembly into position in the vehicle.
  6. Install the heater pipe assembly to the heater core.
  7. 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.

  8. Install the heater pipe assembly retaining bolt.
  9. Tighten
    Tighten the bolt to 16 N·m (12 lb ft).

  10. Install the RH air injection pipe.
  11. Install the RH air injection pipe to RH cylinder head bolts.
  12. Tighten
    Tighten the bolts to 20 N·m (15 lb ft).


    Object Number: 63229  Size: SH
  13. Install the RH air injection check valve to LH cylinder head bolt.
  14. Tighten
    Tighten the bolt to 20 N·m (15 lb ft).

  15. Connect the hose and hose clamp to the RH air injection check valve.

  16. Object Number: 621749  Size: SH
  17. Install the heater pipe bracket into position.
  18. Install the heater pipe bracket retaining nut.
  19. Tighten
    Tighten the nut to 10 N·m (89 lb in).


    Object Number: 296265  Size: SH
  20. Install the heater inlet and outlet hoses to the heater pipes.
  21. Using the J 38185 , install the heater hose clamps.
  22. Align the heater hose clamps as shown.

  23. Install the intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical.
  24. Install the battery heat shield. Refer to Battery Heat Shield Replacement in Engine Electrical.
  25. Refill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.