The IAT sensor advises the ECM of changes in intake air temperature (and therefore air density). As air temperature of the intake varies, the ECM, by monitoring the voltage change, adjusts the amount of fuel injection according to the air temperature.
TESTING
See Figures 1 and 2
Unplug the electrical connector from the IAT sensor, then remove the sensor from the air cleaner.
Fig. Fig. 1: Submerge the sensor tip in water and check for the proper resistance between the terminals
Using an ohmmeter, measure the resistance between both terminals. Refer to the chart for the proper resistance reading.
Fig. Fig. 2: Intake Air Temperature (IAT) sensor temperature-to-resistance graph
If the resistance is not as specified, replace the sensor.
REMOVAL & INSTALLATION
Remove the air cleaner cover.
With the ignition OFF, unplug the electrical connector.
Push the IAT sensor out from inside the air cleaner housing.
To install:
Install the sensor, making sure it is properly placed and secure.
Connect the wiring harness, and install the air cleaner cover.