Originally Posted By: stockrex
it that hand calculated? the dic can be quite inaccurate at times.
Actually, the DIC is the more accurate method. It knows exactly how far the vehicle has travelled and the amount of gas that goes into the engine. Hand calculations are inaccurate due to the various levels of "full" when you "fill" the tank. With Fords, IIRC the DIC covers the last 500 or so miles so it can be slow to adjust if you start lots of highway or city, etc. I know I can "influence" the MPG used by the app on my phone by playing with the fill level. However, over time the DIC and the manual calculations get quite close.