For 1990-2009 cars

### Removal Procedure

Notice: Use care when handling the coolant sensor. Damage to the coolant sensor will affect the operation of the fuel control system.

1. Turn the ignition OFF.
2. Remove the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement .
3. Drain the coolant to below the level of the engine coolant temperature (ECT) sensor. Refer to Cooling System Draining and Filling .
4. Disconnect the ECT sensor harness connector.
5. Remove the ECT sensor.

### Installation Procedure

Notice: Use care when handling the coolant sensor. Damage to the coolant sensor will affect the operation of the fuel control system.

Notice: Replacement components must be the correct part number for the application. Components requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are identified in the service procedure. Some replacement components may come with these coatings already applied. Do not use these coatings on components unless specified. These coatings can affect the final torque, which may affect the operation of the component. Use the correct torque specification when installing components in order to avoid damage.

1. Coat the sensor threads with sealer GM P/N 1050805, or equivalent.

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 ECT sensor.

Tighten
Tighten the ECT sensor to 20 N·m (15 lb ft).

3. Connect the ECT sensor harness connector.
4. Install the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement .
5. Refill the coolant system. Refer to Cooling System Draining and Filling .