Hi,

I suspect that my IAT probe could be defective, i.e. giving a temperature that is too high or too low, but not enough to trigger the check engine light.

Does somebody know how to check it ? for example, if I unplug it, what resistance should I read at room temperature ?

Thanks in advance,

 

if you have access to a scan tool it would be easy to check. With the car completly cold(ie before it is started in morning) plug in the scan tool and read what the iat senor is showing. if it is the same as the outside air temp then it is working.