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.
Removal & Installation
- IAT/MAF sensor electrical connector
- IAT/MAF sensor retaining screw (2 required)
- IAT/MAF sensor
- Disconnect the battery ground cable.
- Disconnect the intake air temperature/mass air flow (IAT/MAF) sensor electrical connector.
- Remove the IAT/MAF sensor retaining screws. To install, tighten to 53 inch lbs. (6 Nm).
- Remove the IAT/MAF sensor.
- To install, reverse the removal procedure.
IAT Sensor Pin Testing
This pinpoint test is intended to diagnose the following:
Voltage values calculated for VREF equal 5 volts. These values can vary by 15% due to sensor and VREF variations.