Intake air temperature (IAT) sensor (models produced before 2000)
Note: On models produced since 2001, this sensor is integrated into the mass air flow sensor (see paragraph 6).
Removal
1. The intake air temperature sensor is a thermistor (a resistor whose resistance value changes in response to changes in temperature). Changing the resistance value has a direct impact on the output voltage signal from the sensor to the ECM. As the sensor temperature decreases, the value of its resistance increases. At increase temperature sensor resistance value decreases (see Figure 7.1).
Figure 7.1. Intake air temperature sensor resistance versus temperature.
Failure of the inlet air temperature sensor and its circuits will cause the corresponding fault code to be stored in the ECM memory (see paragraph 2).
2. Make sure the ignition key is in the OFF position.
3. Disconnect the wiring connector from the intake air temperature sensor (see Figure 7.3).
Figure 7.3. Intake Air Temperature (IAT) Sensor Location (shown by the arrow) — 1996 model.
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4. Remove the sensor from the air filter housing.
Installation
5. Installation of the intake air temperature sensor is carried out in the reverse order of its removal.