Hi, just went for a drive and noticed that my speedo was at 50 MPH when doing a lot less, accelerated on the highway and never went above 50. All other gauges are fine...rpm, miles and fuel. Stopped at a light and it was still at 50. Tapped the gauge screen and it dropped down a bit. When I turned the engine off it was at 25 mph. Thoughts? It's a 2000 flexfuel SE.