Ford Mustang 1989-1993 Repair Guide

Intake Air Temperature Sensor



The Intake Air Temperature (IAT) sensor is a variable resistor which changes in response to intake air temperature. The resistance decreases as the surrounding air temperature increases. This temperature signal is sent to the Engine Control Module (ECM). The IAT sensor is located at the intake port or exit port of the air cleaner or in the intake manifold.


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Fig. Fig. 1: IAT sensor circuit

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Fig. Fig. 2: IAT sensor performance chart

With ignition OFF , disconnect the IAT sensor. Measure the resistance across the sensor connector terminals. If the reading for a given temperature is about that shown in the table, the IAT sensor is okay.