GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1998 🢒 Tracker - 4WD 🢒 HVAC 🢒 HVAC Systems - Manual 🢒 Air Conditioning Evaporator Core Replacement

Removal Procedure
  1. Discharge and recover the refrigerant. Refer to Refrigerant Recovery and Recharging .

    2. Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  2. Disconnect the negative (-) battery cable.

    3. Caution: This vehicle is equipped with a Supplemental Inflatable Restraint (SIR) System. Failure to follow the correct procedure could cause the following conditions:

       • Air bag deployment
       • Personal injury
       • Unnecessary SIR system repairs
    In order to avoid the above conditions, observe the following guidelines:
       • Refer to SIR Component Views in order to determine if you are performing service on or near the SIR components or the SIR wiring.
       • If you are performing service on or near the SIR components or the SIR wiring, disable the SIR system. Refer to Disabling the SIR System.

  3. Disable the SIR. Refer to Disabling the SIR System in Restraints.
  4. Remove the blower case. Refer to Blower Motor and Fan Replacement .
  5. Remove the evaporator inlet and the outlet pipes at the bulkhead by loosening the pipe nuts.
  6. Remove the evaporator case mounting nut on the engine side of the bulkhead (near the refrigerant pipes).

    7. Object Number: 345590 Size: SH
  7. Remove 2 bolts (3) and the right-side instrument panel center support (2).

    8. Object Number: 345592 Size: SH
  8. Loosen the evaporator-to-heater connector band (3). Slide the band onto the heater case.
  9. Remove the drain hose from the evaporator case.
  10. Disconnect the A/C compressor control module (2) and the evaporator temperature sensor electrical connectors.
  11. Remove the SIR harness loop from around the evaporator case.
  12. Remove the 2 upper bolts and the evaporator case from the vehicle.

    13. Object Number: 345572 Size: SH
  13. Separate the upper case (1) and the lower case (3) halves by disengaging 5 retaining clips (2) and 1 screw.
  14. Remove the evaporator pipe retaining clamp from the lower case.

    15. Object Number: 345594 Size: MH
  15. Remove the evaporator (2) from the lower case (5).

    16. Object Number: 345596 Size: SH
  16. Remove the expansion valve (3) from the evaporator by removing 2 nuts.
  17. Remove the evaporator thermistor from the evaporator.

Installation Procedure

    Object Number: 345596 Size: SH
  1. Install the evaporator thermistor to the evaporator.
  2. Coat new O-rings with 525 viscosity mineral oil.
  3. Install the new O-rings to the expansion valve pipe fittings.

    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.

  4. Install the expansion valve (3) to the evaporator (1). Secure with 2 nuts.

    5. Tighten

        • Tighten the large expansion valve pipe fitting to 35 N·m (26 lb ft).
        • Tighten the small expansion valve pipe fitting to 13 N·m (115 lb in).

    Object Number: 345594 Size: MH
  5. Install the evaporator (2) to the lower case (5). Secure with the evaporator attaching screws.
  6. Install the evaporator pipe retaining clamp to the lower case.

    7. Object Number: 345572 Size: SH
  7. Connect the evaporator case halves. Secure the upper case (1) and the lower case (3) halves with 5 retaining clips (2) and 1 screw.

    8. Object Number: 345592 Size: SH
  8. Install the evaporator case to the vehicle. Secure the installation with 2 bolts and 1 nut.

    9. Tighten
    Tighten the evaporator case mounting bolts and nut to 15 N·m (11 lb ft).

  9. Install the SIR harness loop to the evaporator case.
  10. Connect the A/C compressor control module and the evaporator thermistor electrical connectors.
  11. Connect the evaporator case drain hose.
  12. Connect the evaporator case-to-heater case connector band (3). Slide the band on from the heater case and tighten.

    13. Object Number: 345590 Size: SH
  13. Install the blower case. Refer to Blower Motor and Fan Replacement .
  14. Install the right-side instrument panel center support (2). Secure the installation with 2 bolts (3).
  15. Install new O-rings to the evaporator pipe fittings. Coat the new O-rings with 525 viscosity mineral oil.
  16. Connect the evaporator inlet and outlet pipes at the bulkhead. Secure the connection with the pipe nuts.

    17. Tighten

        • Tighten the evaporator inlet pipe nut to 35 N·m (26 lb ft).
        • Tighten the evaporator outlet pipe nut to 45 N·m (33 lb ft).
  17. Enable the SIR. Refer to Enabling the SIR System in Restraints.
  18. Connect the negative (-) battery cable.
  19. Evacuate and recharge the air conditioning system. Refer to Refrigerant Recovery and Recharging .
  20. Operate the A/C system and test for refrigerant leaks. Refer to Leak Testing .