Alright, here'* the deal. I got a 93 w/ 150K miles. Car has been great up until the last few days. When i am in park, i can hear the engine accelerating and deccelerating for a few minutes. When i shift to drive, it jumps as if i was accelerating. It can go pretty fast w/o me even touching the accelerator (2nd gear at least). When it suddenly stops self-acceleration, the check engine light comes on. the shuts off quickly. and its back to normal. These occurances are very random and can happen at anytime. Also, at red lights, it is a very rough idle with sudden jerks at times w/ the car accelerating itself again. Any details that I have left out? How can this be fixed? I think it may be a sensor but i'm not too sure, and i'm not that car savvy. Also i don't know how to get codes on that car so if anyone wants to provide some DETAILED intructions preferably w/ pictures, it would be helpful (same if it is a sensor that needs to be changed). Thanks

Oh yea, and nothing is pushing down the accelerator or anything like that.

I suspect out of adjustment TPS, or bridged/broken TPS wires.

Start here.

http://www.bonnevilleclub.com/techinfo/?article=34

If your car has a MAP sensor,unplug it and seeif the problem improves.If so I'd be looking to replace it.

I had this problem and it was due to a broken down tensioner idler puilley. also had throttlebody cleaned. Now I have similar problem with much less severe symptomes. I had the TPS replaced but it still seems to be an issue.