I might be out of my league but i dont' remember ever seeing a MPG on my '94. And i know 94-97 all have the same dash. If your speedometer doesn't move neither does your odometer. The speedometer drives the odo. I'd say your speedometer gauge is bad. It happened on my '94 and i know tons of people who its takin a crap on of those years. If the car drives fine, and you get no code for the VSS its a sure bet your speedometer is crappin out.