Q: How to test and replace the Intake Air Temperature (IAT) sensor on Cadillac ElDorado and Fleetwood?
A: The Intake Manifold Temperature (IMT) sensor is a thermistor that measures the temperature of the air entering the engine. It has a high resistance at low temperatures and vice versa. The PCM supplies a 5-volt signal to the sensor and measures the voltage to calculate the incoming air temperature. The sensor signal is used to adjust spark timing based on air density.