What’s more efficient, idling your car or switching it off and then restarting it? Doesn’t it require more fuel to restart an engine?
My daughter and I still argue about this. I switch my engine off if waiting for a passenger or am obviously going to be in wait mode for longer than 10 seconds with the exception of stoplights. So who’s right?
Today’s cars use electronic fuel injectors, which control the amount of gas delivered to the engine when you start the car. As a result, no fuel is wasted at startup. So unless you drive a dinosaur with a carburetor, turn off your car instead of idling.
What’s the harm?
- Idling contributes to climate change by releasing carbon monoxide, nitrogen oxide, sulfur dioxide and benzene into the atmosphere.
- Idling for 10 seconds uses more fuel than restarting the engine. Frequent restarting has little impact on engine components like the battery and the starter motor. Wear caused by restarting the engine is estimated to add $10 per year to the cost of driving, money that will likely be recovered several times over in fuel savings from reduced idling.
- Idling wastes fuel. Every 2 minutes a car is idling equals the same amount of fuel it takes to drive about 1 mile.
- Idling contributes to a host of health problems: asthma attacks, impaired lung function, heart problems, and even death.
- Idling is another form of noise pollution.
- Idling is not good for your engine. Excessive idling can damage your engine components, including cylinders, spark plugs, and exhaust systems. Fuel is only partially combusted when idling, leading to build up of fuel residues on cylinder walls that can damage engine components and increase fuel consumption.
- Idling is not an effective way to warm up your vehicle, even in cold weather. The best way to do this is to drive your vehicle. Today’s car engines need no more than 30 seconds of idling on winter days before driving away.
More than 25 states plus the District of Columbia have already enacted idling laws. For an updated list see Compendium of Idling Regulations.
- Arizona
- California
- Colorado
- Connecticut
- Delaware
- District of Columbia
- Florida – effective 12/14/2008
- Georgia – pending
- Hawaii
- Illinois
- Maine
- Maryland
- Massachusetts
- Minnesota
- Missouri
- Nevada
- New Hampshire
- New Jersey
- New York
- North Carolina – pending
- Pennsylvania
- Rhode Island
- South Carolina
- Texas
- Utah
- Virginia
An alternative to idling is to park your car, walk inside, do your business and then walk back to your car. Now there’s a concept.
Resources:
- American Transportation Research Institute: Compendium of Idling Regulations
- California Energy Commission: Should I shut off the motor when I’m idling my car
- Climate 411: When to turn off your engine
- Slate: Is an Idle Car the Devil’s Workshop?
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Welcome to Verda Vivo. My name is Daryl Warner Laux.
What a nice post once again Daryl !
I hate people who idle their cars… In France, it is considered that cars shouldn’t idle not ten seconds as you do but a minute. In any case, idling your car is bad for your money, your environment et caetera.
you summed up the situation very well. Hope you had a nice weekend. I just got home after two days spent with the family…
I have wondered and wondered and wondered about this! THANK you so much for disspelling some of the common urban myths you hear about the whole “more to start up” philosophy and such… I’ve had one person say “You know, the wear and tear you put on by starting it up and turning it off is more damaging than to let it idle”… Any comment on that?
Again, thank you!
My daughter’s boyfriend even idles his car at the gas pump. Yikes! His ignition is messed up since someone stole it but still, I’d rather not get blown up.
Ashley Sue – The cost of stopping and starting the car adds $10 per year to maintenance costs. When compared to the amount of gas you save, it’s a nit.
Thank you both for your comments! ~ Daryl
We did a post about this canadian association called Idle-free. They do lots of things to raise awareness about the importance of stop idling, including interviewing mechanics in order to address false myths about idling. You can see this post and the interviews right here:
http://www.tdicurious.ca/2008/11/letting-your-engine-idle-the-myths/
Normand, Thanks for the comments and the link to your post. I don’t understand why these myths still abound when, with very little effort, you can find information on the internet to dispel it.
I agree with you that IDLE-FREE is fast becoming the new smoke-free. ~ Daryl
i was wondering if there are any native american tribes that have enacted anti idling laws?