Get Quartz in your inbox

Free daily briefing on global business news.

5 car mistakes mechanics wish you’d stop making

How to avoid common car advice that can lead to bigger problems, from using hot water on your windshield to ignoring warning lights and strange noises

Kate Ibragimova / Unsplash

Cars have a funny way of turning simple advice into expensive problems. Someone hears that water works just as well as washer fluid, that an old car is automatically a future classic, or that a strange noise is probably nothing to worry about. The tip gets repeated enough times, and suddenly it sounds like common knowledge.

The problem is that cars are not especially forgiving of shortcuts.

Reader’s Digest rounded up some of the worst car advice mechanics and automotive experts have encountered, and some of it sounds almost reasonable at first. That is what makes these myths worth knowing. The mistake is often not obvious until something freezes, cracks, wears out or becomes much more expensive to repair.

Some bad advice involves saving a few dollars on routine maintenance. Other tips are more dramatic, such as pouring water into an engine or improvising a broken exhaust with whatever happens to be nearby. There are also seemingly harmless habits that can cause trouble over time, such as using the wrong number when checking tire pressure or waiting for rain to clean a dirty car.

The good news is that most of these mistakes are easy to avoid. You do not need to become a mechanic or memorize every detail of your vehicle. You just need to know which shortcuts are worth skipping.

Here are five pieces of car advice Reader’s Digest says you should leave behind, along with the safer approach to take instead.

Water is not a good substitute for windshield washer fluid

Thibault Valjevac / Unsplash

It can be tempting to fill the washer-fluid reservoir with water when you run out of the real stuff. After all, both liquids can make a windshield wet. But that does not mean they do the same job once they are inside your car.

Reader’s Digest notes that washer fluid is formulated to clean the windshield and withstand colder temperatures. Water does neither job particularly well by comparison. In freezing weather, the difference becomes much more important.

Water can freeze inside the reservoir and the hoses........

© Quartz