Unless you are trying to defrost the windshield or warm the interior of your car, idling is not required for today’s vehicles. In most cases, idling longer than 30 seconds is unnecessary. The best way to warm up your car’s engine is to drive gently at the start. Remember, a vehicle gets zero miles per gallon when idling and the result is lower fuel economy and wasted money.
The idea of idling before driving dates back to when cars were built with carburetors. With new fuel-injection technology, complex computer systems and thinner synthetic oils, drivers don’t need to warm up their cars before hitting the road.
According to the Environmental Protection Agency (EPA), “When a car idles for more than 30 seconds, it has several negative effects, such as increasing air pollution unnecessarily, wasting fuel and money, and causing excessive wear or even damaging a car’s engine components, including cylinders, spark plugs, and the exhaust system. Contrary to popular belief, idling isn’t an effective way to warm up most car engines.”