Ford Taurus/Sable 1996-1999 Repair Guide

Intake Air Temperature Sensor



See Figure 1

Click image to see an enlarged view

Fig. Fig. 1: The tip of the IAT sensor has an exposed thermistor that changes the resistance of the sensor based upon the force of the air rushing past it

The Intake Air Temperature (IAT) sensor determines the air temperature inside the intake manifold. Resistance changes in response to the ambient air temperature. The sensor has a negative temperature coefficient. As the temperature of the sensor rises the resistance across the sensor decreases. This provides a signal to the PCM indicating the temperature of the incoming air charge. This sensor helps the PCM to determine spark timing and air/fuel ratio. Information from this sensor is added to the pressure sensor information to calculate the air mass being sent to the cylinders. The IAT is a two wire sensor, a 5-volt reference signal is sent to the sensor and the signal return is based upon the change in the measured resistance due to temperature.


See Figures 2, 3 and 4

Click image to see an enlarged view

Fig. Fig. 2: Measure the resistance of the IAT sensor across the two sensor terminals using a suitable DVOM. Compare the readings to the temp/resistance chart in this Section

Click image to see an enlarged view

Fig. Fig. 3: The IAT sensor can be monitored with an appropriate and Data-stream capable scan tool