You could be waiting in your car to pick up a friend or collect children from school and as it’s just for ‘a short while’ be tempted to leave your engine running. According to a study by Renault, a surprising 60 per cent of drivers are unaware that it is illegal to leave your car’s engine idling while you wait, even for a few minutes. Rule 123 of the Highway Code clearly states ‘You must not leave a vehicle’s engine running unnecessarily while that vehicle is stationary on a public road.’ By doing so, and ignoring the detrimental impact this has on emissions, you can receive a fixed penalty of between £20-80. You may want to keep your motor running simply for convenience, for example, if parking is difficult or to keep your heating or air-con on, but by leaving your engine idling for just 10 seconds, you waste more fuel than restarting it. Renault’s study also claims that every minute a car is idling it produces enough emissions to fill 150 balloons. The best advice for all new drivers is be mindful, and steer clear of the idling habit.