The car starts up and idles decent. Unless I turn the AC on it stutters and rpm drop from 800ish to 450ish and then back up and it sounds like its about to die. Acceleration hiccups too from 1-3k rpms and its worse when the ac is on but it still happens with the ac off. It started yesterday and its getting worse as the day goes by. The only thing I can think of is I resistored the IAT... or a bad fuel filter? Any ideas lets start with the basics?

 

update...

I got a new fuel filter installed and had the place clean the injectors too...
The transmission fluid is brown! and there is air bubbles in it and supposedly a leak... would this cause the engine to hiccup during acceleration?

Also still having studders when I turn the ac on.

 

You need new plugs and wires. Most times the fuel filter is not the problem and is a waste of money that a shop will try to milk out of you.