Have a question that makes no sense to me.. I have a Scangauge II connected to my FEH and placed it in trip mode to show current MPG.
I left my son's house this evening and drove the 20 miles or so home. Before starting out I reset both the dash MPG and the Scangauge to zero. They stayed in step for about 6 miles, then the SCII reading started pulling ahead. By the time I arrived home the SCII stowed about 38.5mpg and the dashboard showed 31.4. A difference of 1 or 2 mpg might be ok - but 7 mpg... Am I missing a setup in the SCII, it is fairly new and I don't have a lot of experience with it. Any ideas ???

 

Have you calibrated the distance and fill settings? Check pages 16-20 of the manual.

 

Take a look at the miles driven; between the trip odometer and the SG trip computer. They're probably not in sync, hence the higher reading.