Ok so all this started happening after I put some fuel injection cleaner in a new tank of gas. At first, every once in a while the engine would just die. Some people had said it might be the fuel filter had gotten clogged from all the debris the cleaner picked up, so I had it replaced. That same day it got worse, a lot worse. Now it constantly stalls, it dies when I first start it up, it stalls after i back out, and it stalls every time i stop, or go slow enough so the rpm's go below 1000. Now I'm not going to lie, I was being foolish and decided that in an effort to save money, I would use regular fuel instead of premium. I used about 3 or 4 tanks of regular. Today I went to the gas station and filled it up with premium from halfway, so now it's half regular and half premium, or pretty much just mid-grade. It started running better for the most part, I drove it around the base trying to get the new fuel to start going to the engine, i was able to sit and idle for a little while and then drive off without a problem, i could turn the car off and back on without a problem, it only died twice in the 15 minutes i was driving it around (a LOT less than it normally would have), and it would almost die but it fought back and revved itself to get it going again. Anyway i'm still not positive on whether or not it was the gas, or a more major problem. So do you think it sounds like it is the gas? And if so, could the engine have possibly gotten hurt from using regular fuel for so many tanks? Thanks.

Hm... If it my money, I would bet on the Idle Air Control - IAC. Check the harness.

Getting any codes?