Why It Might Be Illegal to Warm Up Your Car Where You Live

Next time you’re thinking about starting your car to get it all nice and toasty on a frosty winter morning, you might want to think again. It could be illegal!

There are laws in 30 states and the District of Columbia that prohibit drivers from letting their vehicles idle, like when you warm your car up in the morning to knock some of the chill out of your commute. In addition to individual states, a number of cities and counties have similar laws on the books aimed at preventing cars from idling.

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What’s the Purpose of Anti-Idling Laws?

These statutes aren’t meant to make your winter mornings more unpleasant. The goal of anti-idling laws is to prevent air pollution. Vehicle exhaust releases harmful chemicals, soot and gasses like nitrogen dioxide that can aggravate asthma and allergies and contribute to cardiovascular and respiratory diseases. If you’ve ever lived in a city with air quality advisories or a thick layer of smog hanging heavy in the air, you can appreciate the intent of these anti-idling laws.

Cars and trucks are also a major source of greenhouse gases, contributing to ozone and haze regionally and to the larger problem of climate change. According to the Environmental Protection Agency, every gallon of gas burned pumps about 20 pounds of greenhouse gasses into the atmosphere.

What States Have Laws Against Idling?

It’s important to note that the laws, as well as the penalties, differ from place to place. For example, you could face a fine as high as $5,000 for letting your car idle for more than three minutes in Washington, DC. But in Pennsylvania, you can let your car run for as long as 20 minutes if the temperature is below 40 degrees. Here’s the list of states with anti-idling laws, according to the EPA’s website:

Arizona
California
Colorado
Connecticut
Delaware
District of Columbia
Georgia
Hawaii
Idaho
Illinois
Kansas
Maine
Maryland
Massachusetts
Michigan
Minnesota
Missouri
Nevada
New Hampshire
New Jersey
New York
North Carolina
Ohio
Oregon
Pennsylvania
Rhode Island
South Carolina
Texas
Utah
Vermont
Virginia
West Virginia

Because the laws can vary from state to state and city to city, you should always check to see what the statues are where you live.

But Aren’t You Supposed to Warm Up Cars in the Winter?

Back in the old days of carburetors, it was helpful to let the engine run for a few minutes before starting your drive. But that’s not the case with today’s fuel-injected vehicles. Most cars only need about 30 seconds to circulate oil throughout the engine, about the time it takes you to fasten your seatbelt and queue up your playlist, according to JD Power.

The best way to warm up a car is by driving it. Sure, it may be a little cold at first, but your car will warm up faster, and the heater and defrost will work better, with the car in motion.

Idling Wastes Fuel

Still not convinced about skipping the warm-up? Think about your bottom line. Idling wastes gas. In fact, idling for 10 seconds burns more fuel than turning off the engine and restarting it. Gas isn’t getting any cheaper, so it makes sense to save where you can.

Does Idling Damage the Engine?

Idling itself doesn’t damage the engine specifically, but it does add to the wear and tear. Those minutes spent idling add up, and you’ll need to get the oil changed sooner the more you idle.

Sources

Environmental Protection Agency (EPA): “Compilation of State, County, and Local Anti-Idling Regulations”
EPA: “Greenhouse Gas Emissions from a Typical Passenger Vehicle”
North Carolina Department of Environmental Quality: “Why Is Idling Harmful?”
JD Power: “Do You Need to Warm Up Your Car?”