I have a 2003 Coupe A/T w/ NAV. My gauge cluster goes wacko all the time. MPH and RPM are never correct. Sometimes the gauges go all the way around and back. Fuel and Temp are also off the charts. The trip odometer and main odometer are also showing something different each time you start the car.

Here's the kicker. I'm only able to drive about 40-45 mph at max all day long. Someone has told me its because the NAV and the gauge cluster are reporting two different speeds to the computer. It causes the computer to limit my top speed. Any truth to this?

Sounds like I will need a new gauge cluster to solve it all? Any ideas or thoughts are appreciated.