GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2008 🢒 Cobalt 🢒 HVAC 🢒 Heating, Ventilation, and Air Conditioning 🢒 Air Conditioning Evaporator Core Replacement

Tools Required

J 39400-A Halogen Leak Detector

Removal Procedure
  1. Remove the HVAC module from the vehicle. Refer to HVAC Module Assembly Replacement .

    2. Object Number: 1548653 Size: SH
  2. Remove the heater core cover heat stakes with a small chisel.

    3. Object Number: 872606 Size: SH
  3. Remove the heater core.

    4. Object Number: 877661 Size: SH
  4. Unsnap and open the passenger compartment filter door.
  5. Remove the lower HVAC case screws.

    6. Object Number: 877662 Size: SH
  6. Remove the lower HVAC case.

    7. Object Number: 877663 Size: SH
  7. Remove the evaporator core.

Installation Procedure
  1. If replacing the evaporator core, add polyalkylene glycol (PAG) oil to the evaporator core. Refer to Refrigerant System Capacities .

    2. Object Number: 872568 Size: SH
  2. Install new seal washers to the evaporator core fittings.
  3. Install the thermal expansion valve (TXV).

    4. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the TXV bolts.

    5. Tighten
    Tighten the TXV bolts to 7 N·m (62 lb in).


    Object Number: 877663 Size: SH
  5. Install the foam seals to the evaporator core.
  6. Install the evaporator core into the HVAC module assembly.

    7. Object Number: 877662 Size: SH

    Important: Make certain that the orifice plate is correctly positioned in the HVAC module. Make certain that the lower HVAC case is properly positioned and is fully seated on the HVAC module before installing the screws. Be sure to install all lower HVAC case screws.

  7. Install the lower HVAC case.

    8. Object Number: 877661 Size: SH
  8. Install the lower HVAC case screws.

    9. Tighten
    Tighten the screws to 1.8 N·m (15 lb in).

  9. Close and secure the passenger compartment filter door.

    10. Object Number: 872606 Size: SH
  10. Inspect the foam heater core seal on the lower HVAC case. If damaged, replace using Kent Industries adhesive black foam tape P/N 46480 or equivalent.
  11. Install the heater core into the HVAC module.

    12. Object Number: 877660 Size: SH

    Important: Make certain that the heater core cover is properly positioned and is fully seated on the HVAC module before installing the screws. Be sure to install all heater core cover screws.

  12. Install the heater core cover.
  13. Install the heater core cover screws.

    14. Tighten
    Tighten the screws to 1.8 N·m (15 lb in).

  14. Install the HVAC module into the vehicle. Refer to HVAC Module Assembly Replacement .
  15. Evacuate and charge the refrigerant system. Refer to Refrigerant Recovery and Recharging .
  16. Leak test the fittings using the J 39400-A .
  17. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .
  18. Fill the cooling system. Refer to Cooling System Draining and Filling .