GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 1998 🢒 Grand Prix 🢒 HVAC 🢒 HVAC Systems - Automatic 🢒 HVAC Module Assembly Replacement

Removal Procedure
  1. Remove the air cleaner and duct assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 3.1L or Air Cleaner Assembly Replacement in Engine Controls - 3.8L.
  2. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
  3. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  4. Remove the fuel injector sight shield cover if equipped with 3.8L . Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical-3.8L or Fuel Injector Sight Shield Replacement in Engine Mechanical-3.8L.
  5. Remove the cross vehicle beam. Refer to Instrument Panel Tie Bar Replacement in Instrument Panel, Gauges and Console.
  6. Disconnect the A/C lines at the evaporator block fitting. Refer to Suction Hose Replacement .
  7. Disconnect the heater hoses at the heater core. Refer to Heater Hoses Replacement (3.8L) or Heater Hoses Replacement (3.1L) .
  8. Remove the HVAC module to dash nuts.
  9. Disconnect the vacuum hoses.
  10. Disconnect the electrical connectors.

    11. Object Number: 283714 Size: SH
  11. Remove the HVAC retaining nuts to the dash panel.
  12. Remove the HVAC retaining bolts to the dash panel.
  13. Remove the HVAC module.

    14. Object Number: 176870 Size: SH
  14. Remove all of the outer HVAC module seals (1,2,3).

Installation Procedure

    Object Number: 176870 Size: SH
  1. Install all of the outer HVAC module seals (1,2,3).

    2. Object Number: 283714 Size: SH
  2. Install the HVAC module.

    3. 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 HVAC module to dash bolts and nuts.

    4. Tighten
    Tighten the HVAC module bolts and nuts to 10 N·m (89 lb in).

  4. Connect the electrical connectors.
  5. Connect the vacuum hoses.
  6. Install the Cross vehicle beam. Refer to Instrument Panel Tie Bar Replacement in Instrument Panel, Gauges and Console.
  7. Connect the heater hoses at the heater core. Refer to Heater Hoses Replacement (3.8L) or Heater Hoses Replacement (3.1L) in Engine Cooling.
  8. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  9. Install the A/C lines at the evaporator block fitting. Refer to Suction Hose Replacement .
  10. Recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
  11. Leak test the A/C system. Refer to Leak Testing .
  12. Install the fuel injector sight shield cover if equipped with 3.8L. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical-3.8L or Fuel Injector Sight Shield Replacement in Engine Mechanical-3.8L.
  13. Install the air cleaner and duct assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 3.1L or Air Cleaner Assembly Replacement in Engine Controls - 3.8L.