Description & Operation
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 resistance decreases as the air temperature increases. This provides a signal to the ECM indicating the temperature of the incoming air charge. This sensor helps the ECM to determine spark timing and air/fuel ratio. The IAT is threaded and screws into the intake manifold.
- Disconnect the negative battery cable.
- Remove the engine cover.
- Unplug the electrical connector at the sensor.
- Using an ohmmeter, measure the resistance across the two terminals of the sensor. The sensor resistance should be less than 1340 ohms with the engine at normal operating temperature. Replace the sensor if not within specifications.
- To test the wiring harness, unplug the ECM; test the harness between the proper ECM connector terminal and the sensor connector. Also check the harness between the proper ECM connector terminal and the sensor connector. If resistance is more than 1 ohm, repair the wiring harness.
- Install the engine cover.
Connect the negative battery cable.