Debunking The Top Idling Myths

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The following article is sponsored by UCAIR.

By Utah Clean Cities for UCAIR

This winter you’ve probably heard a lot about the importance of reducing idling, especially during inversion season. In fact, not idling is one of the most important things we can all do to help clean up the air.

Right now there are a lot of myths out there about idling that we’d like to put to rest so that we can all breathe a little easier:

Myth: The best way to warm up your car is to let it idle for several minutes.

Fact: No. Idling is not an efficient way to warm your vehicle, even in cold weather. A slow drive-off during the first mile is the best way to warm a vehicle’s transmission, tires, suspension, steering the wheel bearings.
Myth: Frequent re-starting of my vehicles engine will cause serious damage.

Fact: Re-starting has little impact on engine components like the battery and starter. You can actually reduce wear and tear when you turn off your vehicle, rather than idling. Excessive idling can damage your engine’s internal parts.

Myth: Turning my vehicle off and on uses more gas than if I just leave the engine running.

Fact: Just 30 seconds of idling uses more fuel than re-starting the engine. If you’re going to stop for 20 seconds or more (except in traffic) shut the engine off. Some experts estimate 10 seconds is the break-even point.

Myth: Pollution from an idling vehicle doesn’t have a significant impact to our health and environment.

Fact: Actually, the impact of idling pollution is quite significant because the toxins emitted from idling vehicles impair our lungs and heart. Idling fumes have been linked to asthma, decrease lung function, cardiac disease, cancer and other serious health problems. Children, the elderly and those with respiratory ailments are most at-risk. Prolonged exposure can possibly lead to death.

Myth: Idling doesn’t waste fuel.

Fact:  An hour of idling time consumes approximately a gallon of fuel or more per hour depending on the vehicle.

5 Reasons Not to Idle

  1. Reduces greenhouse gas emissions
  2. Decreases fuel costs and dependency
  3. Improves air quality and contributes to a clean environment
  4. Decreases need for unnecessary engine maintenance
  5. Improves overall health of citizens

Idling is a habit we all easily can break if we just take a moment and think about the overall effects of the pollution emitted into our air. 50 percent of Utah’s air quality problems come from vehicles. Our vehicles are an everyday necessity, but it’s important to use them wisely. You can do your part – Turn Your Key and Be Idle Free!

For more information about other ways you can improve air quality this inversion season visit and



    Idling doesn’t cause any more damage than running the engine at any other speed. Will repeated starting affect the life of a starter motor? That’s a silly question any child could answer.

    • bob

      Liberals are children, and assume the rest of us are as well.

      OF COURSE using the starter more often wears it out sooner. Duh. How stupid do they think we are?

      Starting up has other bad effects as well. There is zero oil pressure when the engine is started. There will always be a lack of lubrication in the first couple of seconds after a restart.

      Idling for long periods of time is unhealthy for gasoline engines, but that doesn’t apply to most people. In most cases shutting off the engine and restarting it DOES cause more wear and tear. Engines that run continuously will last more operational hours than engines that are restarted frequently. That’s almost as obvious as the “starter motor” thing.

      Diesels, on the other hand, LOVE to idle. And because they are not stoichiometric (i.e. they don’t require a constant air-fuel mixture…..there is no throttle plate, so they’re “wide open” all the time) they run EXTREMELY lean at idle. An idling diesel burns a phenomenally tiny amount of fuel.

      As an illustration: I once owned an old Mercedes diesel, and did a procedure to clean out the injector system. You put a pint of solvent into a jar, dip the fuel intake and outlet lines into the jar, and let the engine run on the solvent until it’s used up. The engine took THREE HOURS to go through a pint of fuel. And that was a relatively inefficient, old-school diesel. A modern one would take even longer. And idling diesel is just an air pump. The emissions are so clean it’s hard to believe.


        @JEFF KROGUE
        We’re not paranoid about our cars breaking down because we’re smart enough to know that repeated use of the starter motor doesn’t increase it’s longevity. We also don’t buy into your “the sky is falling” fables.

  • bob

    Fact: Cars that have “automatic start-stop” features, and shut off at stoplights, have extra heavy-duty batteries and starter motors in order to handle the severe duty cycles.

    So to claim that starting the car doesn’t cause wear and tear on the starter and battery is obvious untrue.

    Depending on how long the engine is shut off the emissions system can revert to “open loop” operation, and require a warmup period after restarting before it becomes fully operational again. Exactly how long that takes depends on a lot of factors. To suggest that “idling is bad” without adding a long list of qualifiers is a lie of omission.

    Idling at stoplights has no effect on air quality. Warming your car in the driveway has very little effect. It DOES encourage car theft. And it is actually true that immediately driving off at a moderate speed, taking it easy until the engine warms up, is the best policy.

    “No Idle” laws are just liberal meddling. They love to control every aspect of peoples lives. It lets them know who’s really in charge.

  • Craig Smith

    I call bullsh**t on most of this article. Common sense about wear and tear will answer most of these questions better than the liberal who wrote this article and expected anyone to believe it.

  • Michael Nance

    I wouldn’t believe anything that UCAIR puts out on this or any subject that has to do with air pollution they are trying to screw over everyone but the biggest polluters like the factories they pay them to much money so they have to make it look like they are doing something so they pick on the ones that pollute the least not the most so don’t believe anything put out by UCAIR.

  • Stewart McDonald

    Ever notice had the ultra-rich liberals fly around in their private jets ……. to promote their global warming fears?

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