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

INTAKE AIR TEMPERATURE (IAT) SENSOR
The Intake air temperature (IAT) sensor is located in the air cleaner. The IAT sensor is a variable resistor whose resistance changes as the temperature of the air flowing through the air intake changes.

The Engine Control Module (ECM) uses the IAT sensor input to adjust fuel injector pulse width. When the temperature sensed is cold, the ECM enriches fuel mixture by increasing injector pulse width; as the air warms, the injector pulse width time is shortened.