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8 Car Myths Debunked: Separating Fact from Fiction

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Cars are complicated machines, and plenty of myths exist about how to keep them running smoothly. 

From exploding gas tanks to the magic of premium gas, get ready to be amazed and amused as we debunk some of the most common car myths out there. 

Did you fall for any of these?

1. I Should Warm Up My Car Before Driving 

This may be something you learned when you first laid your hands on a steering wheel. However, idling your car before driving is no longer necessary in this age of fuel injection. 

While it’s true that some oils and vehicle parts may not function at max capacity until the engine is warm, idling the engine isn’t an efficient way to heat it. Some components, such as wheel bearings and transmissions, can only start warming up when the car is moving.

So, idling your car is usually a waste of time, and it’s better to warm up your car by driving gently for the first few kilometers. This is true for modern vehicles, even in frigid weather.

2. Proper Tire Pressure is Shown On the Tire’s Sidewall

This one’s a common misconception. The number you see on the side of your tire is actually the maximum safe pressure the tire can hold and not the recommended pressure for your specific vehicle. 

You can check your owner’s manual or the a decal on your driver’s doorjamb to find the correct pressure for your car’s tires. Make sure to maintain the proper air pressure in your tires to improve braking, handling, and fuel efficiency.

3. I Should Replace All My Tires At Once

While it may seem logical, replacing all four tires when only one needs replacement isn’t necessary. As long as the new tire is the same size, model, and brand as the other tires, you typically don’t need to spend extra money to replace them all.

4. A Dirty Car Saves More Fuel than a Clean One

This one isn’t a total no.

The reasoning behind the idea is based on dimpled golf balls — which can fly faster than smooth ones as the dimples disrupt air around them, creating a small wake that reduces drag. 

Mythbusters” ran a full-scale test, applying a layer of clay to a car; one set with a smooth clay surface and another with dimples pressed into it. The respective fuel efficiencies were calculated as 26 and 29 miles per gallon.

So, technically, you can improve fuel efficiency with a dirty car. But how will you make sure you get a dimpled pattern each time? Best to get that car washed.

5. I’ll Get More Gas if I Refuel in the Morning 

Some think getting gas in the morning when it’s cooler outside will give them more bang for their buck. The idea is that since gasoline is denser in cooler temperatures, they’ll get more fuel per gallon pumped. 

However, gasoline is stored in underground tanks, so its temperature stays pretty consistent regardless of the temperature outside. 

So, whether you fill up in the morning or afternoon, the gas you get will have the same density — no need to set your alarm super early for a gas run to save some cash.

6. Premium Fuel Makes My Car Run Better

No, it doesn’t. Not if your engine isn’t made to run on it. 

Premium gas might be more expensive, but that doesn’t mean it’s purer or cleaner than regular gasoline.

The truth is, premium gasoline is only for certain cars that require less combustible fuel. 

If your car’s engine needs a higher-octane level, then yes, you should use premium. But if not, don’t waste your hard-earned money on it! You can always check your owner’s manual to confirm your vehicle’s gasoline needs.

7. A Bullet to the Gas Tank Will Cause the Car to Explode

You know those action movies where a car gets shot and explodes into flames?

Well, turns out that’s just a myth. “Mythbusters” tested it out and found that normal bullets won’t cause a gasoline tank to ignite or explode. 

But there’s an exception. 

They did find that a special type of bullet called a tracer round can potentially cause a fire — if it ignites with air friction after being shot from a far enough distance. Even then, the chances of an explosion are pretty slim unless the tank is already heavily damaged by multiple tracer rounds. 

So, in reality, it’s pretty unlikely that a single bullet will turn a car into a fiery wreck like in the movies. Still, we’d advise you not to try this at home!

8. Car Doors Stop Bullets 

Another common movie trope involves using a car as cover during a gunfight. “Mythbusters” tested this, too, and found that it wasn’t true. 

While some bullets may not have enough force to penetrate the steel, relying on a vehicle for protection isn’t a safe choice. You’re probably better off hiding behind earth, stone, or steel — though we’d never wish you such unfortunate circumstances.