* Engine Coolant Temperature (ECT) Sensor: This sensor is the most common one and is located in the engine block, usually within the cylinder head or near the thermostat housing. Its exact location can vary slightly depending on the year and specific model of the vehicle. You'll likely need to consult a repair manual specific to your vehicle's year and model to pinpoint its precise location.
* Cylinder Head Temperature (CHT) Sensor (Sometimes): Some 4.2L V6 engines might have a CHT sensor, but it's not as consistently used as the ECT sensor. This sensor is typically located in the cylinder head. Again, a repair manual will be essential for its location.
To find the sensor:
1. Consult a repair manual: This is the most reliable way to locate the sensors. A Haynes, Chilton, or factory service manual will have diagrams and clear instructions.
2. Use an online parts diagram: Many online auto parts stores (like AutoZone, Advance Auto Parts, etc.) have diagrams you can look up using your vehicle's year, make, and model. These diagrams often show sensor locations.
3. Visual inspection: Once you have a general idea of where to look from the manual or diagram, carefully inspect the engine block and cylinder head near the thermostat housing. The sensor is typically a single-wire or two-wire sensor with a connector. Be cautious of hot surfaces!
Remember to always disconnect the battery negative terminal before working on any electrical components. If you're not comfortable working on your engine, it's best to take your vehicle to a qualified mechanic.
