Save Your Engine: 5 Tips For Preventing And Cleaning Carbon Buildup

The world is looking mighty volatile these days, so there are plenty of reasons why you should be concerned with your car's engine longevity. Whether you're trying to sustain a higher-mileage car to avoid a new car payment or you're looking for a used car to avoid paying an arm and a leg for a brand-new car, one of the easiest and most important things to consider is a phenomenon called carbon buildup.

Many modern internal combustion vehicles use what's called direct injection to maximize efficiency and minimize emissions while still producing sufficient power. A side effect of this advanced technology is a predisposition to carbon buildup, which is when over the course of thousands of miles of operation, gunky carbon deposits build up on some of the most integral engine components, the intake valves.

The negative effects of unmitigated carbon buildup can include poor fuel efficiency, loss of horsepower, check engine lights, misfires, excessive emissions, and more. Thankfully there are several different ways of preventing carbon buildup, and ways to address carbon buildup if it has already occurred.

A phenomenon called "blow-by" can both be a cause and an effect of carbon buildup inside of a direct-injection engine, and it's especially prevalent in turbocharged direct-injection engines. Blow-by is a natural side-effect of the combustion process that occurs when unburned fuel and oil vapor that can blow past the piston rings and oil seals, and back up into the crank case of the engine where it causes build-up. It's more prevalent in turbocharged direct-injected engines because additional oil can leak past the turbo seals, exacerbating the issue.

Oil catch cans can help prevent that oil and unburned fuel from being recirculated through the intake manifold where it gathers to cause carbon buildup. The catch can captures the contaminants, and filters the air re-entering the intake manifold to theoretically ensure that no blow-by reaches anything it's not meant to. High quality catch cans can be opened and drained to maximize their longevity and efficacy, and the longevity of your car's engine.

Another area where direct-injection engines differ from conventional port-injected engines is their unique and specialized fuel injector design. Direct-injection engines do just what the name suggests; they inject the fuel directly into the combustion chamber to ensure that precisely enough fuel is used with each combustion cycle to optimize combustion while minimizing fuel usage.

In order to do their job in the most efficient manner, the injectors in a direct-injected engine operate at very high pressures to atomize the fuel as it's squirted into the chamber for combustion to produce the most efficient burn of fuel possible. That precise and high-pressure operation requires the injectors to be clean and free of carbon buildup to function properly; luckily, fuel additives or diligently-serviced spark plugs can mitigate that carbon buildup and keep your engine operating as intended. There are many different types of fuel additives, so make sure you're using one that's designed to clean the injectors on direct-injection engines, and follow the instructions on the package. Alternatively, you can have your injectors professionally cleaned.

Does using big brand name gasoline really make a difference? It's a very fair question, especially for the bargain conscious consumer, and unfortunately for that conscious consumer, the answer is yes — but that doesn't mean you're actually spending more money. Most research suggests that filling your car with high-quality gasoline with detergents from the brand-name gas station will help mitigate carbon build-up, even on direct injection and turbocharged direct-injection engines. While it may be a higher price at the pump, you may end up preventing thousands of dollars worth of damage later down the road.

All gasoline sold in the U.S. must meet the EPA's minimum standard for the amount of additives that must be added to fuel to lower pollution and maintain engine performance, but the "top tier gasolines" you hear about go above and beyond those minimum requirements. While the term additives may sound bad, these additives are what keeps your engine free of carbon deposits and operating at optimal levels. In the video above, the folks at Donut Media found that using top-tier gas can also help clean preexisting carbon buildup in an engine, so it's not too late. If you're worried about carbon buildup, spring for the top-tier gas.

If you're especially concerned about carbon buildup or if you recently purchased a higher-mileage direct-injected car and you want to address the issue as soon as possible, you're left with a choice between two labor-intensive practices: walnut blasting and chemical stripping. Unfortunately neither method is particularly simple or quick to perform on your own unless you're a professional, since both require access to your engine's tender insides. We'll start with the most obscure sounding method of walnut blasting.

Walnut shell blasting media is a cleaning method that basically sandblasts your intake manifold, but you're shooting small fragments of walnut shells through the ports of your engine into the intake manifold to strip away and rid your engine of that gunky, baked on carbon buildup. It's likely that this will require your engine to be dropped out of your vehicle, so even if you have it performed professionally it will be pricey and time consuming.

Chemical stripping doesn't sound quite as interesting as walnut blasting, but it can be the more accessible solution for someone who wants to perform this significant maintenance task at home since not everyone has access to the tools necessary for walnut blasting. Before you attempt a procedure like chemical stripping or walnut blasting, you must turn your engine to make sure the valves are all closed across the engine. If not, whatever method you're using may end up allowing contaminants into the combustion chamber and ruin your engine.

Once you're sure all the intake valves are closed, you can pour whatever chemical you're using into the intake, and let the solution soak for a while to hopefully begin to break down and loosen the nasty carbon deposits on the valve. After it has soaked for a while, you can begin scraping everything to get rid of the carbon, kind of like the dentist using that horrible pick to scrape the plaque off your teeth. When you feel that you've scraped off all that you can scrape off, soak up the chemical or suck it out, then blow out the intake ports with compressed air. It may be necessary to repeat the process to get everything squeaky clean.