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Air Temperature Sensor ( Ambient / Intake ): Description and Operation

Intake Air Thermosensor (Dynamic Chamber):






The Intake Air Thermosensor, located in the intake air system dynamic chamber, detects intake air temperature.

The ECU uses this input in its calculations for fuel injection quantity and pressure regulator control.

Sensor resistance and the voltage signal to the ECU vary with intake air temperature. The input signal at 20°C (68°F) is approximately 2.5V.

Normal sensor resistance measurements are as follows:

K OHMS AIR TEMP.

29.7 - 36.3 25°C / 77°F
10.5 - 12.9 50°C / 122°F
3.3 - 3.7 85°C / 185°F

The computerized control system on this vehicle utilizes a second intake air thermosensor located in the airflow meter. Refer to AIRFLOW METER in this section.