However, conversely:
If you DO go until the pump shuts off each time (yes, I know it is slightly different at each pump) for LONG enough, your shut off time would begin to average. Your mpg readings over a PERIOD of time, would be your average, still.
It may read SLIGHTLY higher, or SLIGHTLY lower than if you were diligently filling to the EXACT level each time. But it will be the same readings, over time, regardless of which pump you used.
Reiteration:
"Exact science" approach may lead to a more definite number.
"shut off" method will, inevitably, give a different number, though slightly lower. Each pump will be slightly different, but after a length of time, the "differences" will be averaged out, and your "lower" readings will still maintain themselves (while being slightly lower than the exact method..)
Ray
