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

PURPOSE
Measure temperature of intake air and provide PCME with signal used in regulating fuel injection quantity, idle speed, ignition timing, and emission controls.

LOCATION
Integral with air flow sensor.

OPERATION
Sensor is a negative temperature coefficient thermistor. As temperature increases, resistance decreases. Cold air is more dense than warm air. PCME measures sensor resistance via a reference voltage to calculate intake air temperature.