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What do bug spray, black pepper, bar soap, drinking straws, and pennies have in common? Besides all of them being buried somewhere in your junk drawer? These are five surprising household items you can use to fix your car cheaply. Some of these items are just for temporary fixes to get you back on the road. Others are handy diagnostics tools to help you figure out what’s wrong with your car during maintenance. One is even an auto detailing shortcut. But all five are cool, do it yourself car hacks sure to impress your friends.

1. Bug Spray: An Auto Detailing Shortcut

As cars age, their headlight lenses fog over. It is inconvenient and dangerous to drive with dim headlights. Toothpaste and baking soda contain enough grit to polish away fogged headlight plastic, leaving clear lenses. Do it yourself enthusiasts have experimented with bug spray. The DEET used in some bug sprays dissolves plastic headlight lenses. For this reason, you should never spray it directly onto your headlights (or any part of your car). But if you spray it on a paper towel, you can wipe off a fogged layer of plastic and leave your lenses clear. 

The DEET will cling to the lenses, leaving a sticky layer of bug spray and dissolved plastic on your lights. One Youtuber discovered that white vinegar washes away this residue. Unlike professional auto detailing lens restoration kits that polish AND seal your headlights, bug spray is a short-term solution. Learn more about restoring foggy headlights.

2. Black Pepper: A Car Hack For A Leaking Radiator

The first time you see someone pour a teaspoon of black pepper into a leaking radiator and watch the radiator stop leaking, you may call it miraculous. Many old-timers swear by this car hack, even keeping some packets of pepper in the glove box of their classic cars. But everyone agrees that black pepper is a temporary do it yourself stop-leak. So if you have a leak, it’s probably time you changed your car’s radiator.

3. Bar Soap: The Do It Yourself Gas Tank Sealant

You may have heard: never use dish soap to wash your car. But did you know a cheap bar of soap has a place in your toolbox? If your gas tank springs a pinhole leak, rubbing a coat of bar soap over the hole will seal it temporarily. This trick works with holes high on your gas tank that fill the air with gas fumes. A Youtuber found this car hack also works for holes low on your tank that cause gasoline to drip out.

In case you don’t know: gasoline is highly combustible, and a gas tank leak is a serious safety issue. A soap fix is an absolute last resort; replace a rusty tank pronto.

4. Drinking Straws: Insulate A Worn Wire In A Pinch

Blue straws in a glass.  France. (Photo by: Godong/Universal Images Group via Getty Images). Straws are one of our do it yourself car hacks.
Blue straws in a glass | Photo by: Godong/Universal Images Group via Getty Images

Over the years, the insulation on classic cars’ electrical wires wears down. When a wire wears through, it can short out against the frame or other wires. This is another serious issue that can cause your battery to drain, your car to shut down, sparking, and even fire. Unfortunately, electrical gremlins are challenging to diagnose and often not worth fixing. But what if you can find which wire is shorting out and don’t have enough electrical tape to fix it? I once saw a mechanic run into a restaurant for a handful of plastic drinking straws. He then cut them open, wrapped them around a worn wire, and taped them in place. Since that day, drinking straws have had a place in my toolbox: between the black pepper and bar soap.

5. A Penny: Priceless Gauge For Tire Tread Depth

What is a penny worth? If you don’t know whether your tires are safe to drive on, a penny can be priceless. If you have traction and braking issues on wet roads, you probably need to replace your worn tires. But how can you be sure your tires have worn past the legal limit (1/16th of an inch of tread depth)? With a penny, of course!

Place a penny into your tire tread, with President Lincoln’s head facing down. If you can see the top of his noggin, your tires have worn past 1/16th of an inch. On the other hand, if honest Abe disappears into your tire tread, you have more than 1/16th of an inch of tread left. Read up on using the penny test to check your tire depth.


28th May 1954:  A collection of random objects, including a tape measure, a Dunlop pressure gauge, a thimble, and an assortment of tools, keys, buttons, money and matchboxes.  (Photo by Chaloner Woods/Getty Images). Some random items from our do it yourself car hacks.
A collection of random objects. | Photo by Chaloner Woods/Getty Images

There you have it: five car hacks using unexpected household items. Rummage through your junk drawer for a cool automotive tool you can use to impress your friends. Remember, when safety is on the line, it’s best to call a professional who has the proper tools.

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