Questions and Answers

Pontiac Trans Am Third to Fourth Surge Q. Hi Vincent, I was looking around to solve a problem I have with my transmission and I landed on your pages. Very helpful indeed! The car is a 1998 Pontiac Trans Am, LS1 engine, A4 transmission and 40,000 miles. When the transmission shifts from THIRD to FOURTH the rpm goes about 200 up and then down, this for a very short time, less than ½-second, I've scanned it.

It's like if the THIRD clutch would open too fast or the FOURTH too late. I reprogrammed the PCM eliminating the TCC and the problem is gone, but of course the driving feeling is completely different. I like it better now, less aggressive at low rpm, but I don't know if it's negative to leave it like this.

Do I just need more gas or will I experience some other problems? I saw a lot of questions here about stuck TCC solenoids, it looks like mine has the opposite problem, or is it a totally other problem?

Thank you,
Stefano
Switzerland

A. Do you work for a GM dealer there? How are you reprogramming it? Does it have an aftermarket PCM? Here in the states it would set the check engine light off if the TCC were disconnected.

But hey, if it runs better and you have no warning lamps on, leave it alone.