What are the different symptoms between high and low.
Thanks.

The Intake Air Temperature sensor is a thermistor that changes resistance as temperature changes. The resistance goes down as temperature goes up. It should be about 37K ohm at 68 deg F, 7.7k ohm at 140 deg F.

The PCM (computer) uses this info to determine air/fuel ratio, so if it is malfunctioning it will give wrong info to computer, computer will adjust pulse time of injectors based on wrong info.

If it is wildly off, it should light the Check Engine Light.

Can IAT be fixed or it should be replaced once its starting to malfunction.

Thanks.

I don't think so. I don't think that it is easy to take apart without destroying it. I don't think that they are terribly expensive anyway.

I would try to test resistance to see if it is in the right range, preferably at a least two different temperatures. There is a chart in the Haynes manual that lists the resistance at various temperatures.

Take it out of the intake tube, heat some water with a thermometer so you have an accurate temp, dip the end of the sensor in the water and measure the resistance with a DVM. It should compare to readings on the chart. I think that when something like this fails it will be way off, not just a little off, so I wouldn't conclude that it is bad if you get 38k ohm reading when it should be 37k. It will be more like 10M ohm reading when it should be 37k or 0 ohm reading when it should be 37k.

Thanks.