Everyone knows that if you're going to be idling your car for a while, you should turn off the engine to save gas. But how long or short, I've always wondered, is that "while"? I'd heard 3 minutes, I'd heard 30 seconds, but most often I'd heard "Leave your engine on. You don't want to wear it out by starting it all the time."I decided to do some research. It was harder to find an answer online than I thought. Click & Clack only say "If you're stationary for more than a couple of minutes, shut it off, and save gas." The EPA website is vague, suggesting merely to "turn off your engine if you anticipate a lengthy wait." Even the U.S. Department of Energy, Energy Efficiency and Renewable Energy site says "Idling gets 0 miles per gallon. Cars with larger engines typically waste more gas at idle than do cars with smaller engines." And I say, Duh!
At last, the Canadian Office of Energy Efficiency provided me with a rule of thumb, and the answer surprised me. If you're going to be idling for more than TEN SECONDS, they've discovered, you'll save gas by shutting off your engine. Ten seconds?! For goodness sakes! Stoplights can take up to two minutes!
As a matter of fact, in many Swiss cities it is a law that everyone has to turn off their engines at stoplights. Basel was once the dirtiest in Europe (the Rhine river caught fire), and now it's the cleanest.
Americans, however, have their thinking stuck in the 1950s, when it really did use a lot of gas to kick a carburetor into life. Nowadays, though, all cars are made with fuel injection, and starting a warm engine is nothing. Ask your mechanic, and they'll shrug. Starting and stopping more often will wear on your starter, but the money you'll save on gas will help you replace it a few months sooner, and the emissions you save will make a big difference.
Kick the idling habit and see what you save. When I tried it the first time, I was amazed to see that I had gotten nearly 30 more miles on that tank than usual. Thirty more miles -- that's more than one gallon of gas, that's three or four bucks in my pocket per tank. And if each gallon of gas creates 20 pounds of CO2, imagine what a difference an anti-idling movement could make in America!
Even drivers of gas-guzzlers can join the "Homemade Hybrid" movement by downloading free, funny window posters and getting armed with information. No one will believe you that it's only ten seconds!
Please bring this story to the attention of Car Dealers near you!