Many of us are in the habit of warming up the car in the winter, but you may be surprised to learn that it’s completely unnecessary.
Driving warms a car faster than idling. Because of the efficiency of modern fuel injection, idling is not actually an effective way to warm up the car. It warms up faster if you just drive it.
Idling also hurts your car. Idling forces an engine to operate in an inefficient and gasoline-rich mode that over time can degrade the engine’s performance and reduce mileage.
It also costs money. The driver of a car with a V-8 engine will waste 20 gallons of gasoline over the course of the year by idling just five minutes a day. That’s over $70 a year.
So next time you think about going out to warm up the car, avoid the urge. And in general, try to cut back on idling to reduce air pollution. If you’re going to be stopped for more than 10 seconds, like waiting in line at the car wash or drive thru, turn the car off. At that point, you waste more money running the engine than you do restarting it!