I've searched and read a bunch of posts about speedo trouble but i havent found the answer i was looking for. i just installed my new motor and i took the car for a drive and i went about 15 miles then the speedo quit. I drove it home and took out the battery and noticed that the plug wasnt connected to the speed sensor. I reinstalled it, took the car for a drive and it worked great. Well, the other day I was driving down the highway and I got pulled over by a county cop. He said I was doing 73 in a 55, but MY SPEEDO READ 60 MPH! anybody else have this problem? is it time for me to spend $51 on a new speed sensor?

Although somewhat unlikely, the cop could have been fabricating those numbers, so don't buy a new speedometer sensor unless you are sure that is what you need to fix the problem. If your speedometer was off by 13 MPH you would probably be able to tell.

I would clock yourself against someone with a late-model unmodified car or truck with a known working (or somewhat accurate) speedometer.

i'll try that and see what happens. i dont know, i guess it seemed like i was going kinda fast but when you look at the speedo and it only says 60 you just take it like it is. i'll see if i have another sensor laying around i could try. Does anybody else have any input?