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The mpg on my car's dash differs from my own fuel consumption calculations - is this unusual?

I have a Jaguar XE, nearly two years old, which averages around 39mpg on the computer set for long periods. 2000 miles ago I decided to check real mpg by checking fill-ups against mileage and was surprised to find a figure of 35.5mpg. Is this unusual?

Asked on 5 October 2017 by JGH

Answered by Honest John
No, it's typical. Car mpg computers always show better than the truth.

Real MPG enables you to register the fuel economy you are actually getting against your make and model of car, its engine and type of transmission.

Every time you enter an average consumption figure against your car, the overall average automatically adjusts to reflect it.

Real MPG
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