Could be. I was going to look at that later when I got home. Do you have a CEL? It is easy to get to the speed sensor. You could just check the connections to start with.

Did you have the Wiring Harness replaced under Recall?

I also found a bunch more articles. They want alot of money to look them up. I am going to poke around some more.

'97 Mercury Mystique GS (Not mine anymore...) Now running a Toyota Matrix XR Red, 16" wheels, Sunroof, VVT-i