Spedometer/Trans Problem

I was driving and all of a sudden my car started having problems. The spedometer would move on its own and the transmission would rev in neutral. I took it to a mechanic and they have replaced 3 parts, one being the vehical speed sensor, and the problem still exists. Also, when it happens, if you hit the dash board, it stops until it acts up again. Anyone have this problem ever? Please help I havn't had my car for a month because they can't figure it out! Thanks!

Ashley

Hi, The speedo itself can cause your problem, Also could be a loose connection at the circuit board on the dash/guages/speedo, or a bad printed circuit board,or a bad ground,or a corrodee/broken wire,,That's just to name a few things...Have Fun.....See Ya, Clay...