It's possible that something was wrong both with the transmission and with the engine, but when the check engine light comes on and they say it is fine and then the car breaks down a few minutes later, that's a problem. Tell them you are going to take it to another shop to get fixed and you are going to sue them to get your money back, unless they want to take it in and fix it. If they offer to take it in, fine. If not, then you know what you have to do.
Answered on Mar 14th, 2014 at 8:36 PM