I am a brand new user of VMSpc and there is definitely a possibility that this is a user problem. When I connected my VMSpc to our RV, I get readings of 4,278,693.0 miles, 232.0 gallons, 45:24 time, 94,244.3 mph, and 18,442.6 mpg in the odometer window. The RV has roughly 44,000 miles on it so these numbers are kind of off the wall. The odometer shows completely different numbers. I triple checked our engine settings to being Cummins 8.3 ISC 350. Any suggestions?