Just recently I got my car back from the mechanic. When I went to have the transmission serviced, they ripped off the brake harness. Now they've finished, but the ABS light, Traction Control light, and Service Engine Light keep coming on. When I brought it back I showed them the dash while I drove back in forth, they said the computer may have just reset itself. Then when I was driving home, the tachometer went to 6000 rpm while i was doing fifty, and the lights on the dash came back on. Could it still be the computer?

Did the engine actualy jump to 6K? If so I would venture to say the jacked up the VSS wires (assuming of course the speedo dropped as well).

The engine sounded like it sped up, and my car didn't shift at 3k like usually.

Watch the spedo if it happens again.