For 1990-2009 cars

### Removal Procedure

1. Drain the cooling system. Refer to Cooling System Draining and Filling .
2. Remove the air cleaner. Refer to Air Cleaner Assembly Replacement in Engine Controls-3.1L.
3. Remove exhaust crossover pipe. Refer to Exhaust Crossover Pipe Replacement in Engine Exhaust.
4. Disconnect the surge tank line fitting from the coolant outlet.
5. Remove the thermostat housing to intake manifold bolts.
6. Remove the thermostat housing outlet and thermostat.

### Installation Procedure

1. Install the thermostat and housing outlet.

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.

2. Install the thermostat housing bolts.

Tighten
Tighten the thermostat housing bolts to 25 N·m (18 lb ft).

3. Install exhaust crossover pipe. Refer to Exhaust Crossover Pipe Replacement in Engine Exhaust.
4. Connect the surge tank line fitting to the coolant outlet.

Tighten
Tighten the fittings to 21 N·m (15 lb ft).

5. Install the air cleaner. Refer to Air Cleaner Assembly Replacement in Engine Controls-3.1L.
6. Fill the cooling system. Refer to Cooling System Draining and Filling .
7. Inspect the system for leaks.