Another high idle problem... tried everything.
I searched the forums too. This was originally my roomates car, he could not figure out the problem, I bought it from him for cheap so I could have a car to drive while I build my mustang. Here's the skinny....
Car idles around 2k, headers get glowing hot. Only codes that came up were running lean, which I am thinking is either actually lean because of a vacuum leak, or possibly clogged cats. Roomate replaced the IAC, didn't fix it. A "mechanic" told him his thottle body was warped, so he got a used one and put it on there with the TPS that came on it and the new IAC. Still idling high. Disconnected battery and EEC fuse for an hour , still high. We sprayed brake cleaner everywhere under the hood, near all intake and TB surfaces, injectors, vacuum Ts, did not notice any change. I tried unplugging the main vacuum feed from the middle-rear of the upper intake, no change.
I can't think of anything else, I would try checking the TPS voltage but I don't know which two to probe, plus it's unlikely that the TPS on both throttle bodies would be doing the exact same thing. Any other vacuum feeds that I am missing? Thanks