Best to set it to cumulative, and then watch the MPG climb as the car accrues the miles... TheMy mpg is currently 54.4 with lots of urban and uphill driving. I recently went on a week long run and only saw around a 1.5 mpg improvement.
The car has covered 2500 (aprox) miles since I collected it and I have yet to reset the mpg calculator.
Is it best to leave it as it is or reset it (or even reset on each start up) to get a more accurate picture ?
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