Car Wont rev past 3000rpm with IAC plugged in

A catalytic converter will run red hot because of it being clogged or a rich condition, not lean because of a vacuum leak. Based on all your codes I think you should have your charging system tested, not only will low voltage cause a host of issues but one of the codes is specifically for the PCM and that it's seeing lower than expected voltage. Theres codes from too many different circuits for so many things to fail at once. If its not something in your charging system causing an issue it must be wiring, possibly bad grounds or hopefully something simple like corrosion on the contacts or the plug for the main harness. The cat could even be glowing because of incomplete combustion due to lack of voltage to the ignition system and its dumping raw fuel into the cat which is designed to burn it off.

But it runs and revs up normally with the iac unplugged? still could cause that issue? and what do you mean charging system?

Strange.... possibly. I've heard of strange things happening because of a faulty alternator. Research the codes and see for yourself. Are they present with the iac disconnected also? Several of them are oxygen sensor circut malfunctions, a few are for the evap system and one is low voltage to the pcm. It's a very unique problem you have and appears to be electrical in nature

yes they are still present. and i don't know where to go from here. car voltage when car off is 11.78v when car on 13.93 and with iac unplugged still getting 13.93v

did you ever figure this out? i am still having issues. same prob

Same exact problem here also, has anyone ever figured this out? Just installed new iac, still wont rev past 3k with it plugged in but revs fine with it unplugged.