I’m working on a 93 thunderbird with a 3.8 in it and no check engine lights are on.
The engine races at about 2500 rpm in neutral, I changed out the TPS but the idle still was way too high.
My first thought was a vacuum leak and I did find one hose that was rotted away. I then tested for vacuum leaks
by spraying some brake cleaner around the intake and all the lines and fittings, but the engine stayed at a constand rpm.
My next guess is the Throttle Air bypass valve.
What do you guys think, or am I heading in the wrong direction.