...replacing the IAT had no effect.

Car is a 99 C5, I installed a new intake tract setup 1.5 weeks ago. Car runs great. Threw these 2 codes today though. Check the intake air temp on autotap...-38 degrees. All right then. Replace IAT with autozone model...no change. Wtf?

What are the chances the Autozone one is the wrong one? I doubt it, it looked similar, same connector, same penetration into the intake tract, blah blah blah.

What now? Is there a fuse for that sort of thing maybe? That's all I can think of. I don't know how or why the wiring would have a problem. Connector looks fine, no pulled out wires, nothing frayed or melted.

Anyone know where the IAT wiring goes? Directly to the PCM I assume, probably behind the engine. Hmmmm. Crap.

Dope

 

Welp, just in case someone ever searches for this - it appears that it is not uncommon to have a bad IAT socket on a C5. I guess the wiring is short, and over time it can pull the wires out. Mine looked fine, but I picked it up from the dealer today and soldered the new socket in, and it works great now. No more codes, no more -38F IAT readings.

GM Part # is 12102620 ($10.48 at GMPD)

Dope