Can You Really Use Coca-Cola To Dissolve Rust On Your Car?

Here's a fun magic trick you can try at home – get a glass of cola, either name-brand Coca-Cola or some knock-off cola from the local grocery store, and a really gross, old penny. Drop the penny into the glass of Coke, and watch as the grossness all magically disappears. This nifty trick results from the phosphoric acids in Coke's formula dissolving build-ups of grimy oxides that arise from a reaction between oxygen in the air and copper in the penny. Just make sure you pour the Coke out into the sink afterward because it is definitely not safe to drink at this point.

Given Coke's apparent corrosion-busting properties, it's not unreasonable to wonder if this sugary concoction could be put to more practical applications than cleaning pennies or giving you cavities. For example, the surfaces of your car, depending on their age and general condition, may be prone to another form of unsightly oxidation, rust. Could a glass of Coke melt that rust off your car the same way it did that penny, and is it worth trying?

In the technical sense, the answer is yes: Coke can clean rust off of a car's metallic surfaces. Just as it does with the grody penny, Coke's phosphoric acids loosen the bonds between rust and the metal beneath, allowing you to scrub it right off.

Here's the problem: remember how that penny needed to be completely submerged in a glass of Coke for several minutes before the oxidation started coming off? It's the same with car rust. To clean rust off your car with Coke, you'd need to completely cover the spot with Coke and keep it that way for a potentially very long time, much longer than it would take to clean rust in traditional ways. If you're performing a little spot clean that only requires a thimble's worth of Coke and a few minutes, that's perhaps workable, but if the rusty patches are especially large, you'd need to remove the metal part from your car completely, and drop it in an entire kiddie pool full of Coke for potentially several days. For regular cleaning purposes, it's obviously less than ideal.

It's also worth noting that Coke can leave a crusty sugar residue on your car after cleaning with it, which can attract bugs. Additionally, the phosphoric and citric acids in Coke can strip away the finish from your car's paint job if left too long, not unlike the enamel of your teeth. Metal is tough, but it's not invincible.

Instead of buying up all the Coke at your local grocery store in pursuit of nontraditional cleaning solutions, it may be better to visit your local automotive store. Car care and hardware brands manufacture a variety of rust removal products, better suited for quicker, cleaner efforts than dumping sugary fizz all over everything.

If you visit the cleaning supply section of your local Home Depot or search for relevant products on Amazon, you can find dedicated rust-busting chemicals such as Formula 88 and Rust-Oleum that can be quickly and easily sprayed or rubbed onto rusty surfaces to loosen up the oxidation without damaging the car. Plus, unlike Coke, these products won't leave any weird residues after the fact. Some rust remover product brands like Turtle Wax also provide a protective layer to the car's surface after removing the rust, ensuring that more rust can't form as easily. That's definitely better than that gross, sugary film that Coke will leave on your car if it's left out in the sun.