GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

  1. Remove the air cleaner and duct assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 3.1L.
  2. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging
  3. Disconnect the ABS modulator electrical connector.
  4. Disconnect the electrical connector from the A/C pressure sensor switch.

  5. Object Number: 491758  Size: SH
  6. Remove the liquid/suction line bracket.

  7. Object Number: 406231  Size: SH
  8. Remove the liquid line nut (1) at the orifice.

  9. Object Number: 82109  Size: SH

    Important: If the expansion (orifice) tube is restricted or plugged, remove the expansion (orifice) tube.

  10. Remove the impacted residues.
  11. Using a heat gun (hair dryer, epoxy dryer or the equivalent), apply heat approximately one inch from the dimples on the inlet pipe. Do not overheat the pipe.
  12. While applying heat, perform the following steps:
  13. 9.1. Use needle-nose pliers in order to grip the orifice tube.
    9.2. Use a turning motion along with a push-pull motion in order to loosen the impacted orifice tube.
    9.3. Remove the orifice tube.
  14. Add 30 ml (1 oz) of Polyalkylene Glycol (PAG) Synthetic Refrigerant Oil to the system.
  15. Lubricate the new expansion (orifice) tube and O-ring seal with mineral base 525 viscosity refrigerant oil and insert into the inlet pipe.
  16. Install tube with the smaller screen (3) first.
  17. Remove the O-rings seals (2).

Installation Procedure


    Object Number: 82109  Size: SH

    Important: Coat the new O-ring seals (2) with mineral base 525 viscosity refrigerant oil.

  1. Install the new O-ring seals (2).
  2. Install the new expansion (orifice) tube with the shorter screen (3) end in first.


    Object Number: 406231  Size: SH

    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.

  3. Install the liquid line nut (1) at the orifice.
  4. Tighten
    Tighten the liquid line nut to 27 N·m (20 lb ft).


    Object Number: 491758  Size: SH
  5. Install the liquid/suction line bracket.
  6. Connect the electrical connector from the A/C pressure sensor switch.
  7. Connect the ABS modulator electrical connector.
  8. Evacuate and charge the A/C system. Refer to Refrigerant Recovery and Recharging
  9. Test the system for leaks. Refer to Leak Testing
  10. Install the air cleaner and duct assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 3.1L.