Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

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LEMON is the spiritual successor to CHARM, I recommend you try it!

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Coolant Temperature Sensor/Switch (For Computer): Description and Operation


The engine coolant temperature sensor constantly supplies the electronic control assembly with a signal reflecting engine coolant temperature. On 1.3L/4-80.8 models, the engine coolant temperature sensor is threaded into the top of the lower intake manifold. On all other models, it is threaded into the engine near the thermostat housing.