Engine Coolant Temperature Sensor Replacement 5.0L, 5.7L

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

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.

1. Disconnect the negative battery cable.

Caution: To avoid being burned, do not remove the radiator cap or surge tank cap while the engine is hot. The cooling system will release scalding fluid and steam under pressure if radiator cap or surge tank cap is removed while the engine and radiator are still hot.

2. Relieve the cooling system pressure.
3. Drain the cooling system below the level of the ECT sensor. Refer to Draining and Filling Cooling System in Engine Cooling.



4. Disconnect the ECT sensor harness connector.



5. Remove the ECT sensor.

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.

1. Coat the threads (only) with sealer P/N 9985253 or equivalent.



2. Install the ECT sensor.

Tighten
Tighten the ECT sensor to 13 N·m (10 lb ft).




3. Connect the ECT sensor harness connector.
4. Refill the cooling system. Refer to Draining and Filling Cooling System in Engine Cooling.
5. Connect the negative battery cable.