How To Clean Your Engine's Throttle Body (Without Removing It)

Our cars depend on many individual mechanical parts and systems, as well as a host of electrical sensors and computers to carry us to and from various destinations. Each of these components serves a critical purpose, and they work together to keep the engine purring and the wheels turning. Most people understand the engine's responsibility when it comes to propelling our vehicles down the road. However, internal combustion engines don't work on their own — they depend, in part, on a precise combination of fuel and oxygen to facilitate the small explosions that give them their power. To accomplish this, your car relies on fuel and air intake systems to deliver gasoline or diesel and oxygen to the engine for combustion. These systems comprise various individual parts themselves, including things like an engine air filter and fuel injectors, and they require routine service to keep them in tip-top shape.

One part of the air intake system that you may overlook — despite its importance — is the throttle body. The throttle body connects to your gas pedal, either via cable in the case of older vehicles or electronics in the case of most newer cars. As you depress the gas pedal, the throttle body opens wider, allowing more oxygen into the engine, while letting up on the gas decreases the amount of air entering the engine, reducing power. It's a sturdy component and generally not something you'll have to replace. However, it can become extremely dirty over time. When that occurs, you may experience engine performance issues. Luckily, cleaning the throttle body is relatively easy. 

If you're interested in learning how to clean a throttle body, we've got you covered. As a former professional mechanic who has cleaned innumerable throttle bodies, I'll break it down. 

Before you can clean your engine's throttle body, you need to locate it and gather a few tools and supplies. For most modern vehicles that use fuel injection (i.e., those without carburetors), the throttle body is located between the engine's air filter and the intake manifold. Older carbureted cars have throttle bodies built into the carburetor itself, and the processes to clean and maintain these components differ from those that we'll be discussing in this article.

Modern throttle bodies are usually aluminum and shaped like a boxy tube or a box with a round opening on each end that connects to the air intake tubing on one end and the intake manifold on the back side. Most throttle bodies also have a throttle body sensor, which will be attached to an electrical connector, and on some vehicles, the mass airflow sensor connects to the throttle body, too. To clean the throttle body, you'll need to disconnect the air intake tubing from the front side of the device to expose the butterfly valve inside. In most cases, the intake tubing attaches to the throttle body using hose clamps, which you can loosen and remove using a screwdriver or a small socket.

After you locate the throttle body and gather the hand tools necessary to disconnect it from the intake tubing, you'll need to collect the rest of your supplies. You can use various cleaners and chemicals for this step. However, the best and safest thing to use is a dedicated throttle body cleaner, like Berryman Throttle Body Cleaner or CRC Throttle Body Cleaner. Besides a cleaning solution, you'll also need some soft rags or towels, some rubber gloves, and a very gentle brush.

After locating your engine's throttle body and gathering the necessary tools, you're ready to get started cleaning the part. You'll need to disconnect the front of the throttle body from the air intake tubing by removing the hose clamps connecting the two components. Use a screwdriver or a small socket to loosen the hose clamp nut and slide the clamp backward down the intake tubing. Then, gently remove the tubing from the throttle body — you may need to wiggle the tubing a bit to get it to break free, so take your time and do so carefully to avoid causing damage. While not entirely necessary, it's also a good idea to disconnect the car's battery any time you're performing repairs or maintenance of this type.

With the throttle body's interior butterfly valve exposed, spray your cleaning solution into the opening and allow it to soak for a few minutes. Put on a pair of rubber gloves to avoid touching the chemicals with your hands, as well as to prevent damaging the throttle body with your skin's oils. Then, gently begin cleaning the interior surface. If your throttle body is electric, you'll need to depress the gas pedal to move the valve while cleaning. If you drive an older vehicle with a cable-operated throttle body, you can move the butterfly valve manually with your hand. For extremely dirty throttle bodies, you can use a soft brush, like a toothbrush, to clean out gunk and carbon buildup. However, be careful not to knock any debris down into the engine while doing so, and don't use anything with hard bristles, like a wire brush. Once the throttle body is clean, work backward to reassemble the intake tubing and reconnect the battery before test-driving your car to ensure it runs smoothly.

Now that you know how to clean an engine's throttle body, you may be wondering why it's important to do so periodically. The throttle body is responsible for augmenting the amount of oxygen that enters the engine based on the pressure you apply to the gas pedal. Unlike other automotive components, like tires, engine oil, and drive belts, the throttle body isn't something that you should typically have to replace regularly — unless it becomes extremely damaged or experiences a malfunction, that is. However, over time, the throttle body can develop a buildup of gunk and carbon. When this occurs, it can reduce your engine's performance and cause things like a drop in fuel mileage or issues like engine misfires.

Those problems are likely to occur because an excessive buildup of grime and gunk inside the throttle body can reduce airflow, interfere with the butterfly valve's movement, and cause the throttle position sensor to collect inaccurate data. Cleaning the throttle body helps address these issues by removing that gunk. As you probably gathered by reading the information above, the process is relatively simple, even if you don't have a ton of automotive experience. Given the benefits that a throttle body cleaning service can provide and the ease with which most people can perform it, there's really no reason to skip this valuable maintenance project.

Automakers don't typically include throttle body cleaning services as part of the recommended maintenance schedule in vehicle owner manuals, but most experts recommend performing the job at around the 75,000-mile mark. If you've never cleaned your engine's throttle body and your car is close to or has already surpassed that mileage, it's probably a good idea to go ahead and do it.

Besides opening up your engine's throttle body and discovering that it's full of gunk and carbon buildup, you may be wondering if there are any other signs that it's time for a throttle body cleaning service. The answer is somewhat tricky. While there are a few signs that can indicate you need to clean your engine's throttle body, many of those symptoms can point to other problems, too. 

Besides mileage, there are some other signs that your throttle body needs some special attention. A dirty throttle body affects your engine's performance in the form of problems like a rough or shaky engine idle, difficulty accelerating, engine misfires, and engine stalling. Remember, though, that various conditions can cause your car to experience these issues. If you encounter them yourself, cleaning the throttle body is an easy and quick fix, but it may not solve all your problems, and you may want to consider visiting a professional repair shop for a deeper inspection.