What are the symptoms of excessive carbon buildup in the combustion chamber?
2 Answers
Phenomena of excessive carbon buildup in the combustion chamber: Difficulty starting the engine when cold, requiring multiple ignition attempts, but normal operation when warm; unstable engine idling, fluctuating between high and low speeds; sluggish acceleration and a feeling of being "stifled" when revving in neutral; reduced driving power, especially noticeable during overtaking, with slow acceleration response and failure to achieve the vehicle's original power; highly irritating and pungent exhaust emissions that severely exceed standards; increased fuel consumption compared to before. Causes of excessive carbon buildup: When the vehicle is frequently driven at low speeds or idling for extended periods, the engine operates outside its optimal efficiency range, particularly in high-gear, low-RPM conditions. The increased engine load causes the governor to control the high-pressure pump to inject more fuel. However, with the throttle opening small and insufficient air in the cylinder, the air-fuel ratio becomes too low for complete combustion. As a result, the hydrocarbons and gum in the fuel are burned into carbon deposits, which remain in the combustion chamber. Diagnostic methods for excessive carbon buildup: Disassemble the engine to inspect for carbon deposits. This method is straightforward but time-consuming and labor-intensive. Moreover, each disassembly and reassembly of components, regardless of the part, will more or less affect their performance and shorten their service life.
I've been repairing cars for over a decade and have seen many engines clogged with carbon deposits. When there's excessive carbon buildup in the combustion chamber, the most obvious symptom is reduced power output – the car feels sluggish when driving, with particularly poor acceleration. Fuel consumption increases significantly; where a full tank used to last 500 km, it might now only get you 450 km, hitting your wallet hard at the pump. Starting becomes difficult, especially in winter, often requiring multiple attempts to get the engine running. At idle, the engine shakes noticeably, creating uncomfortable vibrations you can feel inside the car. Engine knocking is common – that disturbing pinging or rattling sound from the cylinders that makes you worry. Spark plugs get coated in black carbon deposits, causing recurring issues shortly after cleaning. In severe cases, it can lead to engine overheating due to poor heat dissipation, potentially damaging engine components if left unaddressed. What causes carbon buildup? Mostly from frequent short-distance driving or using low-quality fuel. From my experience, regular engine cleaning or using high-quality fuel additives can help prevent these issues – don't wait until minor problems become major headaches.
