96 accord idling problem

I have a 96 accord. I was driving home and the speedometer went to 0 and didnt come back up, even while i was driving. shortly after that the check engine light came on and the car started idling below 500 when i stopped. it never cut off. just kept idling low and the speedometer wasnt working. Can anyone tell me what they think is the problem?

The speedo problem is almost certainly the speed sensor (if you'd tried the cruise, that likely wouldn't have worked either). I think when it happened to me, the check engine light came on too (likely -- a failed sensor is probably a detectable/reportable event as far as the computer is concerned). Not sure about the idle, though.