GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 1998 🢒 Firebird 🢒 HVAC 🢒 HVAC Systems - Manual 🢒 Air Conditioning Evaporator Core Replacement

Removal Procedure
  1. Drain the engine coolant. Refer to Cooling System Draining and Filling in Engine Cooling.
  2. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
  3. Remove the heater core. Refer to Heater Core Replacement .

    4. Object Number: 282922 Size: SH
  4. Remove the temperature control cable bolt.
  5. Remove the temperature control cable from the module.
  6. Remove the bolts from the temperature valve shroud case.
  7. Remove the temperature valve case:
    8. 7.1. Slide the case downward to disengage the upper case clip.
    7.2. Remove the valve case from the I/P.
  8. Use a small hand saw to remove the perforated section of the HVAC evaporator module.

    9. This section will be reused.

  9. Water may leak onto the carpeting when performing this procedure. Place a mat on the passenger side floor.
  10. Remove the A/C evaporator bracket nut (1).
  11. Remove the A/C evaporator bracket.

    12. Object Number: 282943 Size: SH
  12. Remove the accumulator bolt (2) at the module.
  13. Discard the O-ring seal.

    14. Object Number: 282946 Size: SH
  14. Remove the A/C evaporator tube bolt at the module.
  15. Discard the O-ring seal.
  16. Remove the bolts from the A/C evaporator and blower upper case.

    17. Open the case slightly.

  17. Remove the A/C evaporator seal.
  18. Remove the evaporator.
  19. Transfer the A/C evaporator air filter to the new evaporator.

Installation Procedure
  1. Install the A/C evaporator.
  2. install the A/C evaporator seal.
  3. Apply sealer between the evaporator upper and lower case.

    4. Do not use epoxy glue as a sealer.

  4. Install the bolts to the A/C evaporator and blower upper case.

    5. Tighten
    Tighten the A/C evaporator and blower upper case bolts to 1.8 N·m (16  in).


    Object Number: 282946 Size: SH
  5. Install a new O-ring seal.
  6. Install the A/C evaporator tube bolt at the module.

    7. Tighten
    Tighten the A/C evaporator tube bolt to 16 N·m (12 lb ft).


    Object Number: 282943 Size: SH
  7. Install a new O-ring seal.
  8. Install the accumulator bolt at the module.

    9. Tighten
    Tighten the accumulator bolt (2) to 16 N·m (12 lb ft).

  9. Install the A/C evaporator bracket.
  10. Install the A/C evaporator bracket nut (1).

    11. Tighten
    Tighten the A/C evaporator bracket nut (1) to 2.0 N·m (18 lb in).

  11. Position the perforated section of the evaporator module.

    12. Use epoxy glue in order to adhere the perforated section to the module.

    Allow the epoxy to dry.

  12. Use your thumb in order to grade the sealant on the inside and the outside in order to ensure a water-tight seal.
  13. Use the following steps in order to install the temperature valve case:
    14. 13.1. Slide the case upward into position until the upper clip engages.
    13.2. Engage the snap on the left edge of the temperature valve case to the distributor case.
  14. Install the bolts to the temperature valve shroud case.

    15. Tighten
    Tighten the temperature valve shroud case bolts to 2.0 N·m (18 lb in).


    Object Number: 282922 Size: SH
  15. Install the temperature control cable to the module.
  16. install the temperature control cable bolt.

    17. Tighten
    Tighten the temperature control cable bolt to 1.9 N·m (17 lb in).

  17. Install the heater core. Refer to Heater Core Replacement .
  18. Recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
  19. Refill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.