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

ECT/ACT Temperature Sensor Values:

PURPOSE
ACT sensor input is used as a density corrector for airflow calculations and to proportion cold enrichment fuel flow.

LOCATION
Threaded into a cylinder runner of the intake manifold

OPERATION
Sensor is a thermistor device whose resistance changes with changes in mixture (air/fuel) temperature. To sense these variations, the ECA sends a reference voltage to the sensor and measures changes in resistance as mixture temperature fluctuates.

CONSTRUCTION
Sensor construction is similar to the ECT sensor except it is packaged to improve sensor response time.