A motoring guru has issued a warning to petrol and diesel vehicle owners that they could be wasting up to 20% of their fuel with one simple mistake. Opening your car windows feels like a must when driving in warm weather - but above a certain speed, it could hurt your wallet by reducing fuel efficiency. Chris Evans from comparison site Leasing.com cautioned that wind resistance from open windows can drain fuel tanks faster when driving at high speeds. However, when you're driving slower,

Tag-uri: Petrol