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Tanks for the memory

In 1971 I was working as a car salesman. It was a Saturday and I had just filled the tank of my demonstration car. I was in the countryside and I had to stop for a cow on the road. However I was on the blind side of a humpback in the road and a Jaguar XJ6 ran into my rear end at high speed. The tank burst. I believe that because my petrol tank was full, the fumes could not be compressed and explode on impact. Perhaps I am wrong but I keep my tank full when out of town. I think I saved my life and I would rather save it than a few quid over a year.

Asked on 14 August 2010 by BD, via email

Answered by Honest John
The other side of the argument is that a litre of fuel weighs a kilo. 10 kilos extra weight on a car can increase CO2 emissions by 1 g/km. So it follows that driving on half a 60-litre tank can save 3g/km compared to driving on a full 60-litre tank. The difference remains the same as the tank empties.

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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