Causes, hazards, and cleaning of engine carbon deposits

Causes, hazards, and cleaning of engine carbon deposits

As the "heart" of a car, the health of the engine directly determines the performance and lifespan of the vehicle. And "carbon buildup" is one of the most common "chronic diseases" of engines. Whether your car is new or old, understanding the causes, hazards, and cleaning methods of carbon deposits is an essential task.

1、 How is carbon deposition formed?

Carbon deposition is the accumulation of gum, resin, and impurities caused by the incomplete combustion of fuel and lubricating oil under high temperature, high pressure, and oxidation. The main causes include:

Poor fuel quality: Poor quality gasoline contains a large amount of impurities and gum, which are the main culprits in the formation of carbon deposits.

Poor driving habits in congested road conditions: Vehicles are driven at low speeds and idle in urban areas for a long time, and the engine cannot reach its optimal operating temperature, resulting in insufficient fuel combustion.

Burning engine oil ": For old or faulty engines, engine oil will seep into the combustion chamber to participate in combustion, but it cannot be completely burned off, resulting in hard carbon deposits.

Dirty intake system: Failure to replace the air filter in a timely manner can result in dust and particulate matter entering the engine, mixing with oil vapor to form sludge and carbon deposits.

2、 The harm of carbon deposition should not be underestimated

When carbon deposits accumulate in key areas such as the throttle valve, intake manifold, fuel injectors, and combustion chamber, it can cause a series of problems:

Fuel consumption increases, power decreases: Carbon deposits occupy combustion chamber space, change compression ratio, and affect intake efficiency and fuel atomization effect, resulting in a decrease in engine power. To obtain the same power, more fuel needs to be consumed.

Difficulty in cold start, idle shaking: Carbon deposits will adsorb some fuel, causing the mixture to be too lean during cold start, making it difficult to ignite. At the same time, when idling, the engine runs unevenly and the body will experience significant shaking.

Weak acceleration and strong jerking sensation: When sudden acceleration is needed, the engine response is delayed, and it feels like the fuel is not flowing away, even causing acceleration jerking.

Excessive emissions can damage the three-way catalytic converter: incomplete combustion can produce more harmful substances, leading to unqualified annual inspections and damaging expensive three-way catalytic converters.

3、 Comprehensive Guide to Carbon Cleaning

In the face of carbon deposition, we have the following mainstream cleaning methods, which can be selected according to the severity of carbon deposition:

Mild prevention: Fuel additives (cleaning type)

Introduction: Commonly known as "fuel treasure", it is directly added to the fuel tank to clean the oil circuit, fuel injectors, and some combustion chamber carbon deposits as the fuel flows.

Advantages: Low price, simple operation, and can be used as a daily maintenance method.

Disadvantage: Limited effectiveness for severe carbon buildup, only suitable for prevention and mild cleaning.

Moderate cleaning: "Hanging bottle" (intake system cleaning)

Introduction: Using specialized equipment, the cleaning agent is directly injected into the intake manifold in an atomized form to clean the throttle valve, intake valve, and combustion chamber without disassembling the engine.

Advantages: The cleaning effect is better than that of fuel additives, with strong targeting and significant effect on carbon deposition in the intake duct.

Disadvantage: Unable to clean stubborn carbon deposits behind the fuel injector and at the top of the piston.

Deep cleaning: walnut sand cleaning

Introduction: Currently recognized as the most effective physical cleaning method. The walnut sand is sprayed at high speed onto the back of the intake valve through the device, and its impact force is used to break down and suck out the hard carbon deposits.

Advantages: Thoroughly cleaned, has a miraculous effect on stubborn carbon deposits, and can restore the engine to a nearly new state.

Disadvantages: The intake manifold needs to be disassembled, the construction is complex, time-consuming, and expensive.

Summary suggestion: Developing good driving habits, regularly running on highways, and using high-quality fuel and oil are the best ways to prevent carbon buildup. If the vehicle has mild symptoms, fuel additives can be used; If the symptoms are obvious, it is recommended to clean the "hanging bottle"; For vehicles with high mileage (such as over 80000 kilometers) or severe symptoms, walnut sand cleaning is the best choice for restoring power.