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Air Temperature Sensor ( Ambient / Intake ): Description and Operation




LOCATION

The Charge Air Temperature sensor is threaded into the intake manifold plenum.


FUNCTION

The sensor element extends into the incoming airstream to measure the temperature of the air passing through the intake manifold.


OPERATION

The PCM sends out a reference voltage of approximately five (5) volts to the coolant temperature sensor. As air temperature changes, the internal resistance of the sensor will change, causing a varying voltage drop across the sensor. The PCM reads the voltage drop across the sensor as charge air temperature.

The PCM uses this information to calculate the proper injector pulse width and spark advance.