According to the South Carolina Department of Health and Environmental Control (SCDHEC.gov), idling a car for as little as ten seconds actually uses more fuel than turning off the engine and restarting it ! In fact, every minute of idling uses at least 2/10 of a gallon of gas, up to about 7/10 of a gallon for an 8-cylinder engine. If you spend five minutes idling, you'll waste a perfectly good gallon of gas. If gas costs you an average of $3.00 a gallon, that's three bucks pretty much burned up with nothing to show for it. Do that four or five times a week, and you could waste as much as $12 or $15 - enough to buy a pizza, go see a movie, or save in your rainy day fund.
The problem increases in winter because so many drivers believe idling is a good way to warm up their engine. In fact, just the opposite is true, says SCDHEC.gov. To properly warm a vehicle's transmission, tires, suspension, steering, and wheel bearings, it's much better to slowly drive the car as soon as you you start it.
Sure, it's convenient to idle, especially if you're waiting for someone, using a drive-through window, or (ahem) parking illegally. But for cleaner air, healthier kids, and greater fuel savings, keep the idling to a minimum.
WHAT CAN YOU DO TO IDLE LESS?
* If you're going to be stopped at a traffic light, traffic jam or railroad crossing for longer than ten seconds, turn off the engine. (Don't worry - research shows that turning off the engine and then turning it on again several seconds or a minute later doesn't damage it, despite the myth to the contrary.)
* Skip drive-throughs, especially during the busiest times of the day when start-stop traffic is likeliest to be heavy (this means mornings at drive-through donut and coffee shops, lunch time for fast food restaurants, and afterwork for banks). The one drive-through I do use is at my pharmacy; I've learned that a wait for the customer in front of me could take five or ten minutes, and my own service could take equally as long. It's been easy to get in the habit of turning the car off until it's my turn.
* Use a remote car starter sparingly. Yeah, in cold climates, it's a real treat to get into a warm car when it's freezing outside. But ironically, though the air might be warmer, it could actually be more polluted, as well, since outdoor emissions can filter into the car through windows and air intake vents.