When you buy a new car, not only is its exterior nice and shiny, so is the rest of the car. That includes the inside of the engine. As you drive a car, though, there’s a lot of work going on inside the engine that can really dirty it up. The firing of the pistons and general operation can cause carbon deposits to slowly build up inside the cylinders, on valves, and fuel injectors. Over time, this build up of carbon and other nasty gunk can hurt performance and cause your car to be less efficient.

Luckily, there are inexpensive solutions to this problem. Fuel additives can help reduce the amount of carbon build up inside your engine. Keep in mind, if your car is new, you likely won’t need to use these fuel additives, but if you own an older car with a lot of miles on it, studies have shown that the chemicals and detergents in these products do make a difference. Check out the video below from Engineering Explained to get an in-depth look at how these fuel additives function and why they work.

Now that you know how these additives can potentially help your car’s fuel system, it’s important to note that not all of these additives are the same. There are plenty of them out there, but we’ve found you get the best results if you do some research and find ones that come highly recommended from other shoppers. The three options below are some of the best products available.

Sea Foam Motor Treatment

sea foam

Sea Foam Motor Treatment can be found just about anywhere and has a wide variety of uses. You can definitely use it on your car, but it’s also helpful in cleaning engines in just about anything. It’s suitable for both two and four stroke engines and can also be used in diesel engines. Sea Foam does not have the harsh detergents or abrasive chemicals that some other products do. This helps ensure that it won’t damage anything as it cleans.

Buy Now: $13

Lucas Oil Deep Clean Fuel System Cleaner

Lucas Oil

The Lucas Oil Deep Clean Fuel System Cleaner is designed to remove carbon deposits, reduce NOx emissions, and even eliminate knocking and pinging within the engine. If you look around on various online forums it’s clear that Lucas Oil products come highly recommended. The company has a full line of fuel additives but this one, in particular, is supposed to do a good job of getting those stubborn carbon deposits out of your engine.

Buy Now: $7

Royal Purple Max-Clean Fuel System Cleaner and Stabilizer

Royal Purple Max-Clean

The Royal Purple Max-Clean Fuel System Cleaner and Stabilizer does an excellent job of reducing carbon inside your engine. Like the other products on this list, it’s designed in a way as to not hurt vital engine parts while still stripping away any tough grime. While the Royal Purple name generally isn’t as well-known as Lucas Oil or Sea Foam, it’s clear from the customer reviews and online test videos that this is a superior product.

Buy Now: $12