The Engine Coolant Temperature (ECT) sensor's function is to advise the ECM of changes in engine temperature by monitoring the changes in coolant temperature. The sensor must be handled carefully during removal. It can be damaged (thereby affecting engine performance) by impact.TESTING
- Disconnect the engine wiring harness from the ECT sensor.
- Connect an ohmmeter between the ECT sensor terminals.
- With the engine cold and the ignition switch in the OFF position, measure and note the ECT sensor resistance.
- Connect the engine wiring harness to the sensor.
- Start the engine and allow the engine to reach normal operating temperature.
- Once the engine has reached normal operating temperature, turn the engine OFF .
- Once again, disconnect the engine wiring harness from the ECT sensor.
- Measure and note the ECT sensor resistance with the engine hot.
- Compare the cold and hot ECT sensor resistance measurements with the accompanying chart.
- If readings do not approximate those in the chart, the sensor may be faulty.
- Drain the coolant from the system low enough to remove the sensor.
- Disconnect the sensor wiring.
- Using a deep socket, remove the ECT sensor and gasket.
- Install a new gasket to the sensor.
- Using the deep socket, insert and secure the sensor. Tighten to 9-14 ft. lbs. (12-20 Nm).
- Attach the wiring to the sensor.
- Refill the cooling system.