Automakers figured out a long time ago that most people don’t know how to properly care for or operate their vehicles.

“As engineers, we’re tasked with making cars idiot-resistant,” says Steve Ciatti, Ph.D., a mechanical engineer and technical lead at the Argonne National Laboratory. Ciatti laughs as he says this, but he’s not really joking. “We do what we can to mitigate the effect of people doing less-than-optimal things to their machines, but we can only do so much,” he says.

The good news is that, compared to pretty much any other piece of technology you own, your car can handle a lot of abuse. But there are still plenty of mistakes you can make—and probably are making—that shorten your car’s life or sabotage its performance.


YOU WARM UP YOUR CAR IN WINTER BY IDLING IT
Your dad may have taught you to let your car idle for ten minutes before driving it when the weather’s frigid. But when it comes to newer cars—anything made in the last decade or two—idling is not an efficient way to warm up the engine. “Light driving is what warms it up effectively,” Ciatti says. Idling when your engine’s cold could prematurely wear down some of its components by depriving them of adequate lubrication, he says. “You don’t want to jackrabbit right out of your parking space onto the highway either,” he says. A little light neighborhood driving—three to five minutes—is ideal when your engine’s ice cold.

YOU RUN ON EMPTY
When your gas tank is nearly empty, your fuel pump has to work harder to maintain the proper fuel “flow rate,” Ciatti says. “Over time, that can burn the pump out.” Harmful moisture or condensation in your fuel tank may also work its way to your engine if you drive on fumes too often.

YOU SHIFT GEARS WHILE ROLLING
You’re backing up and, while still rolling, you shift into drive. Don’t. “When you shift from reverse into drive, you’re making a lot of stuff that was spinning in one direction reverse and spin in the other direction,” Ciatti says. When you do that without first coming to a complete stop, it creates a lot of strain on your drive train. “Your transmission doesn’t like that,” he says.

YOU DON’T USE YOUR PARKING BRAKE
When you shift your transmission into PARK, your brakes are not engaged. The only thing keeping your car from rolling away is a small pin in the transmission, Ciatti says. “That pin is not designed to hold a lot of weight,” he says. Over time, if you never use your parking brake, that pin can wear out and fail.

But if you’re the type who never uses his parking brake, don’t start after reading this. “If you haven’t been using it, there could be substantial rust on it that will cause sticking,” Ciatti says. You’ll want to take your car to the dealership, or ask the mechanic to check your parking brake during your next oil change, he says.

YOU ACCELERATE AND BRAKE TOO FORCEFULLY
Hammering the accelerator and stomping on the brake are hard on your car’s components, and will wear them down, Ciatti says. Hard acceleration also sabotages your MPG, he says.

Keep an eye on your tachometer, which displays your engine’s revolutions-per-minute, or RPMs. The next time you’re cruising at 55 or 60, check your RPMs. Whatever the tachometer reads, that’s close to where the manufacturer established your ride’s optimal efficiency. When you’re driving around town, you’ll want to keep your RPMs at or below that level whenever possible. “It’ll probably be around 3,000 RPMs for most cars,” Ciatti says.

YOU DON’T PROPERLY INFLATE YOUR TIRES
If the air in your tires is too low, their sidewalls will wear out more quickly, leading to blowouts, Ciatti says. Your MPG will also suffer. On the other hand, if your tires are overinflated, that will hinder their traction and braking power. Check your vehicle’s manual for the proper inflation PSI, and check your tire pressure once a month, he advises.

YOU CHANGE YOUR OIL TOO FREQUENTLY
A lot of drivers follow the old “change your oil every 3,000 miles” line. But thanks to newer engines and better oils, you can go much longer, Ciatti says. “It takes oil time to break in and adapt to an engine, so if you’re changing it constantly, that’s not the best thing,” he explains. Most manufacturers recommend 5,000 miles between changes. But with synthetic oils, you may be able to go longer, he says. If your car has a “fuel life” monitoring system, you can trust that to tell you when you need a change.