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This sensor is is usually located in the airbox or on the airhose between the airbox and throttlebody that pushes into a rubber grommet. Some engines have a metal screw in type located in the engine plenum.
The sensor consists of a thermosistor that is placed into the airstream, as it the air temp gets higher the resistance drops. The ECM supplies the sensor +5V and measures the voltage drop through the thermosistor to determine temperature. Some resistance vs temperature values follow:
*F---------Ohms
210-----------185
158-----------450
104-----------1800
68-------------3400
32-------------7500
-4--------------25,000
-40------------100,700
GM IAT/MAT sensors are notoriously inacurate, they are succeptable to heat soak on the sensor itself and faster flowing air will cool the sensor off sometimes below actual air temp. The sensor is used for air density calculations that factor into fuel delivery.
The sensor consists of a thermosistor that is placed into the airstream, as it the air temp gets higher the resistance drops. The ECM supplies the sensor +5V and measures the voltage drop through the thermosistor to determine temperature. Some resistance vs temperature values follow:
*F---------Ohms
210-----------185
158-----------450
104-----------1800
68-------------3400
32-------------7500
-4--------------25,000
-40------------100,700
GM IAT/MAT sensors are notoriously inacurate, they are succeptable to heat soak on the sensor itself and faster flowing air will cool the sensor off sometimes below actual air temp. The sensor is used for air density calculations that factor into fuel delivery.