I monitored my 40 minute, 25 mile commute to work today. Mixed traffic and average between 65-70 mph. After reaching my destination, these were my readings. The computer read 50.7 MPG The Scangauge II read 65.3 MPG Is there some calibration needed? I'm guessing the computer reading in the car is more accurate. Any thoughts?
the computer is usually a few percent high, resulting in lower mpg at the pump. not sure what's going on with the scan gauge. did you reset the trip meter on the car before starting out?
just to compare drives and meters. if you're looking at instantaneous mpg, the car is 3 seconds behind. if you want to compare mpg for a trip, or a tank, you would need both devices starting at zero.
Are you new to Scanguage? It sounds like you need to calibrate it. The next time you fill up, you should go to Fillup, then hit done, then save. Then at your next fillup, go to fillup and see how many gallons the scanguage thought you used. You adjust that figure to match how many gallons you actually put in your tank.
I've found that my SG-II tracks pretty much the same as the MFD in the car, but I also keep an accurate log of how much fuel into the tank, and how many miles the car is driven, and over time they all correspond pretty accurately (…at least to within amounts that really make no difference) (…but as they say YMMV )
