Idling FAQs

With modern emissions technology and more fuel-efficient cars, why do I have to worry about a small matter like idling?
Newer cars have controls that reduce air pollutants in exhaust. Compared with unregulated vehicles 30 years ago, today's new cars generate 98% fewer hydrocarbons, 96% less carbon monoxide and 90% fewer nitrogen oxides. But one element in tailpipe emissions hasn't been cleaned up - carbon dioxide (CO₂). This is the principal greenhouse gas linked to climate change. Every gallon of fuel that is burned produces about 20 pounds of CO₂, plus small amounts of the powerful greenhouse gases methane and nitrogen dioxide. The bottom line: the more fuel you use, the more CO₂ you produce. And one of the best ways to cut fuel consumption is to avoid idling. After all, it gets you nowhere.

Can I turn someone in for idling?
No. Currently there are no rules or regulation prohibiting excessive idling for the average motor vehicle. If you want to get involved at your school or organization to try and help reduce idling, contact Air.Awareness@deq.nc.gov for more information.

How can only one gallon of gasoline burned by a car or light truck produce 20 lbs of carbon dioxide (CO₂)? 
Two factors contribute to the high output of carbon dioxide (CO₂) per gallon of fuel burned. First, fuel burns in the presence of oxygen that it gets from air. Since air is only one-fifth oxygen, large quantities of air are needed to burn gasoline. Second, gasoline is rich in carbon, which is converted to CO₂ when burned in the presence of oxygen. Because large quantities of air are required to burn gasoline, large amounts of CO₂ are produced. If you're a typical motorist who drives 13,000 miles each year, you're emitting about four and a half tons of CO₂ per year - that's three times the weight of your car!

Is it important to idle my vehicle for a few minutes to warm up the engine, especially in winter?
No. Although this is a common practice among motorists, it's also wasteful and pollutes the air. Tests show that you need no more than 30 seconds of idling to circulate the engine oil before you can drive away on cold days. Anything more just wastes money and produces needless greenhouse gas emissions. Remember, more than the engine needs to be warmed - so do the tires, transmission, wheel bearings and other moving parts. Also, the catalytic converter doesn't function at its peak until it reaches the optimum operating temperature of 806 degrees F (430 degrees C). The best way to warm the engine and all other components is to drive your vehicle.

Will I get a ticket if I idle?
No. Currently there are no rules or regulation prohibiting excessive idling for the average motor vehicle. But if everyone did their part, we could have a healthier environment for all.

Can idling damage my car's engine?
Yes. Because the engine isn't working at its peak operating temperature when it's idling, the fuel doesn't undergo complete combustion. This leaves fuel residues that can contaminate engine oil and damage engine parts. For example, fuel residues tend to deposit on spark plugs. As the amount of engine idling increases, the plugs' average temperature drops, and they get dirty more quickly. This, in turn, can increase fuel consumption by four to five percent. It's a vicious circle of wasted fuel and needless greenhouse gas emissions. Excessive idling can also let water condense in the vehicle's exhaust. This can lead to corrosion and reduce the life of the exhaust system.

How much fuel am I wasting, and how much CO₂ do I produce by idling my vehicle?
The cost of idling your vehicle for 10 minutes every morning can add up. You use about 0.025 gallons of gasoline for every 10 minutes. This adds up to about 10 ounces of carbon dioxide for those 10 minutes. It may not sound like much, but it all adds up. Many people idle in the morning, at the ATM, at the drive-through for lunch, then waiting to pick the kids up from school. How long do you idle each day, each week, each year? And remember, millions of motorists have fallen into the idling trap.

Should I drive-through or walk into fast food restaurants?
Every time you use a drive-through, you waste gas by idling your car. According to Quick Service Restaurant Magazine, the average wait time at a drive-through is around three minutes. Add the minute or two that it takes to place the order, and that means one billion car-minutes spent idling each year in front of fast food restaurants alone! (Not to mention idling at ATMs, banks, and other stores.) Do your part, next time you are at a fast food restaurant, trying the "walk-through" instead.