Why does my car constantly give me different ranges on a full tank?

My 2016 Ford EcoSport 1.5 TDCi said I had 538 miles until the tank was empty when I first filled it. In the summer, it said 600 miles to empty. Tonight, I filled it to the brim and it said 508 miles to empty. Have you any ideas why there is such a difference in the mileage I'm getting?

Asked on 22 November 2017 by Martin Dunne

Answered by Honest John
The estimate is based on your current mpg extrapolated. So if you are driving very economically it will estimate a greater range than if you aren't.
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