95 LSS 88, runs rough when traction control is off

My son's 1995 88 LSS has developed a weird problem, the traction control switch on the dash board has recently started acting up. When properly working you should be able to turn in off or on while driving. Now, if you switch the T/C off while driving, the car starts missing and loses power, and you cannot turn T/C back on unless you stop the car and turn the engine off, I guess the car starts normally in the on position by the computer.

Has anyone else see this? I will probably have to take it to the dealer, because I have no way to trouble shoot this, there are no codes or check engine lites on. Very strange though. Once you shut the car off and restart, it runs fine.

Thanks for any advice!!

Sounds like an issue with the TCM causing the engine to cut back falsely, this will take a comprehensive scan as you say.

Thanks, but I sold her off, someone wanted to buy my car as is, so I unloaded her, she was a good car, had 163,000 miles and it was time to say goodbye before the massive heart attack hit, I got only a grand for it, but saved a few hundred by not fixing the T/C problem. Farewell old workhorse.