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Q. Dear Umbra,

My daughter’s Girl Scout troop wants to start an anti-idling campaign at her school. We need help justifying why a car should be turned off for more than 30 seconds. Although they have found that it saves gas and wear and tear on the engine and other parts, very few people believe that 30 seconds is long enough. Most believe that their starter, in particular, will need to be replaced, thereby reducing the gas savings. Can you point us to definitive information about idling and when and why to turn off your engine? Thanks.

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Brentwood, Tenn.

A. Dearest Kew,

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school bus stop signStop idling (and stop worrying about your starter).madame.furie via flickrIsn’t a car made to last through tens of thousands of stops and starts? You don’t find these same pro-idling people assiduously avoiding frequent car trips in order to lengthen the overall life of their car. I’m missing some piece of the logic train wherein the engine knows that the driver maybe could have chosen to leave it running, and it takes revenge by breaking down sooner.

In my own personal car experience, the failure of starters is more closely linked to car manufacturer than to age or anti-idling. But personal experience is not definitive information, so instead I am going to point you to bossy federal agencies and a helpful nationwide anti-idling campaign.

First, let us reflect on why we are anti-idling. Idling a passenger car is almost always unnecessary, it wastes gas, and it produces myriad air pollutants (as detailed in one of my previous columns). Schoolchildren’s mouths are closer to both engine and tailpipe (by virtue of their height, not because they are licking engines), so these polluting emissions enter their sensitive young bodies with ease. Larger diesel engines, such as would be found in a school bus or delivery truck, have the same issues, only diesel fuel is dirtier than gasoline. Most idling emissions research has been done on these diesel engines, and there are idling regulations now in many states (some include all engines, not just diesel). Tennessee does not appear to have anti-idling regulations.

One helpful resource for you might be Earth Day Network’s No Idling Campaign. It’s based on a Georgia No Idling campaign, is aimed at schoolchildren, and includes toolkits, data collection charts, and lesson plans. In terms of the “definitive information”: Here is a serious refutation of the starter damage myth from the California Energy Commission; some data and resources on school bus idling from the EPA (including curriculum materials); and a short EPA sheet that references the 30-second rule. Another way to look at it is that no reputable source recommends idling.

If you commence your campaign and still have trouble with families worried about the imminent failure of their car, it might be effective to find a reputable local mechanic or car dealer who will vouch for the durability of the starter. The federal government is simply not persuasive enough in some situations — too far away, too easily linked to a disliked leader. A community expert might be just the person you need. Best of luck.