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Coolant Temperature Sensor/Switch (For Computer): Testing and Inspection


To test the Coolant Temperature Sensor, located in the intake manifold, proceed as follows.

Coolant Temperature Sensor:





1. Remove the engine coolant temperature sensor from the intake manifold.

Coolant Temperature Sensor Test:





2. With the sensing portion of the engine coolant temperature sensor immersed in water, check resistance between the two terminals. The sensor should be held with its threaded housing 3 mm (1/8in.) away from the surface of the hot water.
Standard Values
Water Sensor
temperature (°F) Resistance (Ohm)
32..................5.9
68..................2.5
104..................1.1
176..................0.3


3. If the resistance deviates from the standard value, replace the sensor.