Hi, I have a 2003 Monte Carlo ss 3.8L I had just install all the solenoids in my transmission. The Tcc, both shifts solenoids and epc on the valve body. After reassembling the car, I started the car and my engine revved immediately to 3000 rpm and would stay idled at 3000 rpms until I shut the car off.

I disconnected the ground on battery and waited 30 minutes and tried it again. It revved up again but this time about 2000 rpm. While running still I pressed on the gas pedal and it felt like there were some tension. It would rev up higher and lower as I pressed and depressed the gas pedal but not getting any lower than 2000 rpms.

I turned the car off again and disconnected the battery for 15 minutes. When I stared the car again it immediately revved up to 3000 rpm. I shut the car off right away.

I am stuck at this point. I am not sure if I need a IAC or TPS sensor or both. The car ran fine before I changed out the solenoids in the transmission. Could I have did something wrong there?

Would it be the IAC? I've read that FI I disconnect the IAC and start the car it should rev high. Then If I re-connect the IAC and the engine still revs high than the IAC is bad. If the IAC is good it would idle correctly. any truth? Thank you all in advance.

 

I think it just may be the IAC like you say. I had a similar problem on my old car and that was the issue.

However, because it happened right after you had transmission work done, I am not 100% on it.