Will always filling up my fuel tank only halfway mean better fuel economy?

I've just read an article saying that you should always fill fuel up to the top rather than filling halfway or less otherwise it could create issues in the long term when it potentially pumps debris, sediment and air when it's near the end. However, money saving tips have always said you should fill the tank halfway or less because of the theory that more fuel equals a heavier car and a heavier car uses more fuel. What's your take on the matter? And is there a difference in approach depending on if the car is petrol or diesel?

Asked on 20 January 2020 by Leo

Answered by Dan Powell
It's never wise to run a car's fuel tank to the absolute limit. Doing so will cause the detritus, emulsified fuel and excess water to run through the engine and potentially cause a blockage or damage. However, filling it to the brim on every occasion? I'm not sure I agree with this advice for large vehicles as it will make the car heavier and result in higher running costs. If you own a small car (like a Ford Fiesta or Vauxhall Corsa) then this is less of an issue, due to the smaller size of the fuel tank.
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