Car mechanic shares little-known button you should always press before driving

You might think that every new feature in a car is likely to make them better, right?

Well, according to a popular mechanic, there's at least one big feature that you should be doing your best to avoid.

Scotty Kilmer is an American mechanic who has built a huge YouTube channel with quick and funny discussions of cars, mechanical questions and much more, and he now has well over six million subscribers.

In a recent video, he took apart 'stop-start' systems in engines. This is a common feature that lets your car turn itself off during brief pauses (like at red lights) before turning back on when you need to drive away.

The idea here is that the feature reduces carbon emissions by cutting down on the time your car spends idling, but Kilmer is convinced this isn't worth the potential downside.

He explained that the biggest moment of strain on any engine, however modern, is when it starts up - the process of firing up is an intensive one. So, it does indeed stand to reason that a stop-start system makes this happen way more often.

In his words: "Most of the wear on your engine occurs when you start the car. The oil at the bottom of the engine, the oil pump has to spin, pump the oil to the top of the engine, and start lubricating. Every time you shut the car off the oil goes back down, it's got to be pumped back up again. Do you really want to be starting and stopping your car all the time?"

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Kilmer said this would make for shorter lifespans for car engines, and this pretty much only suits car companies, not customers, since it means more frequent repairs and purchases.

Handily, though, his video points out a button that many cars have on their dashboard - typically it has an 'A off' logo or similar on it. This button (or the equivalent on different car brands, which you can most likely find in the vehicle's manual) turns the feature off.

You can use this button if you decide that you don't want to use stop-start, although annoyingly you may find that you have to press it every single time you hop in your car, since it won't be remembered between drives.

But this is just one point-of-view - others might argue that it's worth it for cutting down emissions and potentially saving you some cash on gas.