The speedometer on my 95 civic ex only works about half of the time. It's either bouncing up or down, or it will just go flat for awhile. It never stops working for good, just for a few minutes at a time. I took it to a honda dealership and they suggested that the speed sensor was going out, I had that replaced and it didn't help at all. What else could it be?

 

Just a suggestion... loose wiring harness on the back of the cluster? Is it at random times or when you do something specific

 

I tried messing with the back of the cluster, and everything seems loose, but I think it's like that from the factory. I think it quits working completely randomly, although it does seem to do it more often right after I start the car.