Originally Posted by
Cobrajet
I generally see the same thing. I have tracked actual-to-estimated mpg using "MID-B" religiously since I have owned the car...nearly 100,000 miles. Name any week over the last 3 1/2 years and I can tell you what the MID-B said versus what I calculated. If the economy gauge says 45.5 mpg, the mathed-out result will usually be somewhere between 43.5 and 44.0 mpg.
Sometimes, however, they are nearly identical. If the gauge says 45.5, the calculated result will be 45.6 or 45.3.
Other times they are off by as much as 4 mpg. Not sure why.
My experience has been the same as yours. I reset B at every fill up and every tank is consistently 1-2 mpg lower than the B reading. It has always been this way and I've owned my 2014 CVT from 6k to now which is about 50k.
__________________________________________
View my fuel log 2014 Mirage DE 1.2 automatic: 47.1 mpg (US) ... 20.0 km/L ... 5.0 L/100 km ... 56.6 mpg (Imp)