Why You Shouldn’t 'Heat Up' Your Car's Engine In Cold Weather

iStock/borchee
iStock/borchee

When the inside of your car is no warmer than the frozen tundra outside, it’s easy to believe you need to let your engine “heat up” for a minute or two by idling in your driveway before driving away. The old adage goes that giving your engine time to reach its normal operating temperature is easier on your car than hitting the gas as soon as you turn the ignition on. One 2009 study showed that, on average, Americans believed a car's engine should be left to idle for nearly four minutes in subfreezing temperatures—but it turns out this behavior is not only bad for your wallet and the environment, but your car as well.

In 2016, Business Insider spoke with former drag racer Stephen Ciatti to get to the bottom of this widespread myth. Ciatti has a PhD in mechanical engineering from the University of Wisconsin-Madison and has worked on combustion engines for nearly 30 years, so he knows a thing or two about how to best treat your car. And he says that idling your machine in the cold only leads to a shorter lifespan for your engine.

In older car models that relied on carburetors to run, frigid weather did pose a threat to engine performance. Gasoline is less likely to evaporate in colder temperatures, which would have led to carburetors failing to get the right mixture of air and fuel into the engine. This sometimes caused cars to stall out, and that's likely what led to the practice of heating up our vehicles in our driveways in the winter. But if you’re driving a car that was made in the past few decades, this is no longer something to stress over. Beginning in the 1980s, car companies began replacing carburetors with electronic fuel injection, which uses sensors to calculate the correct mixture of air and fuel to supply your engine with.

When temperatures dip below freezing, your engine is already aware of this and adjusts by introducing more gasoline into the fuel mix. By letting your car idle, you’re subjecting your engine to more gasoline-rich fuel than necessary, and this ends up stripping oil from your engine’s vital components.

"Gasoline is an outstanding solvent and it can actually wash oil off the [combustion chamber's] walls if you run it in those cold idle conditions for an extended period of time," Ciatti told Business Insider. He said this washing action can gradually "have a detrimental effect on the lubrication and life of things like piston rings and cylinder liners." So in the end, what you intend as gentle behavior toward your car’s engine could turn out to be the opposite.

Once your engine reaches a temperature of around 40 degrees it switches back to its regular fuel mixture, but idling doesn’t help it hit that point any faster. According to Ciatti, the fastest way to heat up an engine is to actually drive. But don’t take that as an excuse to go gunning down the driveway: Your engine will take between five and 15 minutes to reach a normal temperature from the moment you hit the gas. Until then, go easy on the pedal to avoid putting additional stress on your engine.

This article originally appeared in 2016.

Amazon's Under-the-Radar Coupon Page Features Deals on Home Goods, Electronics, and Groceries

Stock Catalog, Flickr // CC BY 2.0
Stock Catalog, Flickr // CC BY 2.0

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Now that Prime Day is over, and with Black Friday and Cyber Monday still a few weeks away, online deals may seem harder to come by. And while it can be a hassle to scour the internet for promo codes, buy-one-get-one deals, and flash sales, Amazon actually has an extensive coupon page you might not know about that features deals to look through every day.

As pointed out by People, the coupon page breaks deals down by categories, like electronics, home & kitchen, and groceries (the coupons even work with SNAP benefits). Since most of the deals revolve around the essentials, it's easy to stock up on items like Cottonelle toilet paper, Tide Pods, Cascade dishwasher detergent, and a 50 pack of surgical masks whenever you're running low.

But the low prices don't just stop at necessities. If you’re looking for the best deal on headphones, all you have to do is go to the electronics coupon page and it will bring up a deal on these COWIN E7 PRO noise-canceling headphones, which are now $80, thanks to a $10 coupon you could have missed.

Alternatively, if you are looking for deals on specific brands, you can search for their coupons from the page. So if you've had your eye on the Homall S-Racer gaming chair, you’ll find there's currently a coupon that saves you 5 percent, thanks to a simple search.

To discover all the deals you have been missing out on, head over to the Amazon Coupons page.

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When Does a President’s Term Officially End?

President Jimmy Carter and his wife, Rosalynn, leave the White House after President Ronald Reagan's inauguration ceremony in 1981.
President Jimmy Carter and his wife, Rosalynn, leave the White House after President Ronald Reagan's inauguration ceremony in 1981.
Clawson, Wikimedia Commons // Public Domain

You may be aware that newly elected U.S. presidents take office sometime in January—maybe you even know the inauguration occurs on January 20, specifically. What you might not realize is that it’s technically illegal for a president who’s leaving office to continue serving after that date. As the Twentieth Amendment states, “the terms of the President and Vice President shall end at noon on the 20th day of January … and the terms of their successors shall then begin.”

In other words, a presidential term is exactly four years long, down to the hour. In the three cases where January 20 fell on a Sunday (since the 20th Amendment went into effect), the president took the oath of office in a private ceremony on that day, and the public inauguration was held the following day.

Though the four-year term limit has been in the Constitution from the very beginning, January 20 wasn’t always the start and end date. Until 1933, it was March 4. After the Constitutional Convention adopted the Constitution in September 1788, the old government—the Confederation Congress—ceased operations on March 4, 1789 and the Congress of the United States started running things. Getting up to speed took a little longer than expected, and George Washington didn’t end up getting sworn in until April 30. As Binghamton University history professor and provost Donald Nieman writes for The Conversation, March 4 became the official Inauguration Day starting with Washington’s second term.

A painting of George Washington's second inauguration on March 4, 1793, by Jean Leon Gerome Ferris.The Foundation Press, Inc., Library of Congress Prints and Photographs Division // No Known Restrictions on Publication

By the early 20th century, the long delay between officials winning an election and actually starting the job was causing issues—mostly in Congress. Members of Congress were elected in November, but their first session didn’t start until the following December, a whole 13 months later. Furthermore, their second session, which started the December after that, could only last until their terms ended on March 4. So, in the 1930s, Congress passed the 20th Amendment, declaring that congressional terms would begin and end on January 3, about two months after the election.

The president’s inauguration day got shifted to January, too, and the amendment also explained what would happen if a president hadn’t been chosen by that date. The sitting president wouldn’t just stay in office by default—instead, Congress could either appoint someone to serve in the interim, or it could decide on another way to select someone. That person would serve “until a President or Vice president shall have qualified.” Since that’s never happened before, we don’t know exactly what the process would look like.

As for what the president actually does during their last days in office, it’s not all long lunches and lazy walks around the well-kept White House grounds. There are usually plenty of eleventh-hour pardons to make, and it’s tradition for the president to pen a letter to their successor. President Barack Obama also sent a heartfelt email to his whole White House staff, thanking them for their years of support and encouraging them to continue working to uphold democracy.

[h/t The Conversation]