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

PURPOSE
The Intake Air Temperature sensor threaded into the intake manifold extends into the incoming airstream to measure the temperature of the air passing through the intake manifold.


OPERATION
The Powertrain Control Module (PCM) sends out a reference voltage of approximately five (5) volts to the intake air 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.