Your parents are wrong: Experts say you no longer need to warm up your car

Cars actually warm up faster without idling

January 18, 2019 2:42 PM

Christina Lorey,

Posted: January 18, 2019 2:42 PM

Updated: August 31, 2021 12:26 PM

by Christina Lorey

Your parents are wrong: Experts say you no longer need to warm up your car

MADISON, Wis. — It’s the advice our parents have been giving us for generations: You need to warm up your car before driving when temperatures dip below freezing.

But according to new research, what once was true isn’t any longer. Nowadays, cars can be driven immediately at neighborhood speed. That wasn’t always the case.

Most cars built before 1995 used a carburetor, a device that combined air and fuel. With a carburetor, it was important to let the car idle for a few minutes to make sure the engine would run properly.

But now, the auto industry’s changed over to a fuel injection method that’s eliminated the need for the carburetor, as well as the need to warm up your engine.

AAA recommends letting your car idle for just 15 to 30 seconds, or enough time to fasten your seat belt, adjust your mirrors, and go.

“That’s actually a faster way to get things like heat in your car going faster rather than having your car sit idle, which doesn’t heat it up that fast,” said Nick Jarmusz, of AAA Wisconsin.

Whether or not you choose to warm up your engine, no mechanical damage will happen to your car.

“What was true of cars that were built before the 1990s is not true of cars that are built now,” said Jarmusz. “That’s true of a lot of different things, not just the mechanics of things like warming up your car, but safety features and other things.”

The Environmental Protection Agency agrees with AAA that warming up your car is not only not helpful, but it’s wasteful, too. Idling for more than 30 seconds uses more fuel than restarting your car.

These guidelines don’t mean you should speed off right away, though. All experts agree that drivers should take it easy in the first few minutes of driving, especially when temperatures drop below freezing. AAA suggests driving no more than 45 mph for the first five minutes.

“Your bigger concern is really your battery, which you can’t address at the time,” said Jarmusz. “If your battery doesn’t have enough to crank over in extreme cold temperatures, you’re not going to find that out until it’s not cranking over. That’s why we recommend people get their batteries serviced and checked at the beginning of winter.”

Some major cities, such as Minneapolis, Chicago, and New York are taking this a step further by restricting how long the average driver can idle his or her car. Minneapolis, for example, limits the length of idling to three minutes. If you’re found idling for longer, you’ll have to pay a fine.

AAA estimates the average driver allows their car to idle five to 10 minutes a day. If you multiply that by all the drivers in the country, it adds up to a lot of wasted fuel and money, not to mention air pollution.

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