Intake Air Temperature (IAT) Sensor

The IAT sensor is a thermistor which changes resistance in proportion to temperature changes. Resistance increases as intake air temperature decreases and decreases as intake air temperature increases. IAT sensor inputs air temperature to the PCM. PCM uses IAT information as a correction factor in calculation of fuel, spark and MAF. The IAT sensor provides a quicker temperature change response time than the ECT sensor.

On 5.4L Lightning models, 2 IAT sensors are used. One is located before the supercharger in the intake manifold for standard OBD II/cold weather input. The second is located after the supercharger to provide PCM with information to control border-line spark and to help determine intercooler efficiency.