Shelbyville

Welcome to the club. I had the same issue with my 75mm Accufab.I tried everything. IAC mod. TPS voltage adjustments. Disconnecting the battery. You name it, I did it. American Muscle would not take it back so I sent it to Accufab to look at. The tech told me the TB blade was slightly off center and pitched forward a little too much. I am betting you have a 75mm. Anyway, I told Accufab to remove the 75mm and put on a 70mm and the problem went away after some slight adjustments to the TPS which I don't think made a difference but I did it anyway. I had the same problems you did. When coming to a stop, I put it in neutral and the RPMS would jump to 1500+ and take 3-4 seconds to come down. After swapping to the 70mm from the 75mm, all is well. Did you buy the Accufab combo unit with the TB and plenum together?

One more thing. You are not alone. Just Google Accufab idle hang and see how many hits you get back.

laserredgt

oh ok thanks alot...do you think this might be bad for the engine or just annoying? i mean i noticed alot of gin in the response but i dont wanna mess up the life of the engine...

tim2002gt

Sometimes it takes a couple of days of driving for the car to relearn the proper idle. It took mine nearly a week before it started to idle normally.

Shelbyville

If you have an automatic, it can cause some problems with shifting. Otherwise, its just a pain and something I could not get used to. I finally changed over to the 70mm TB and my problems went away. Something you may want to consider if you have a 75mm. You are not going to lose much, if anything at all, in HP downgrading to a 70mm. It should not take too long for your computer to adjust. If it hasn't in 200-300 miles, it probably won't. Good luck.