My check engine light came on and the code was "intake air temp circuit input high and my odb reader was showing the IAT sensor at -34F. I replaced it and same thing...

I am wondering if its causing the misfire upon startup, I can hear a loud pop almost everytime I start it.

 

It makes the PCM think the ouside air temp is extremely cold, so The PCM makes the AF richer than needed, making for poor performance. If the IAT is good, check the wiring between the IAT and PCM,

 

The wiring looks fine, I will try testing it with my multimeter.
I thought the IAT sensor was bad so I replaced it, but they are both showing around the -34F mark. Ill try to see if I get a reading with it unplugged and test the voltage at the same time. I think I read something like 5 volts is supposed to be supplied.

Hopefully I can get this fixed, and maybe it will fix my multiple misfire issue too!

 

you can test the temp sensor using a ohm meter. look here 4th Gen LT1 F-body Tech Articles

 

Thanks!

 

UPDATE:

Made a jumper wire from the pcm to the sensor, found I had a faulty wire! FIXED!