Is Engine Carbon Removal Necessary?
4 Answers
Engine carbon removal is necessary, and for regular vehicles, the engine typically requires cleaning every 30,000 kilometers. Current technology cannot achieve complete combustion of gasoline, so carbon deposits will form as long as the engine is running. The main locations of carbon deposits include: the combustion chamber, intake valves and their surroundings, the three-way catalytic converter, and the lubrication system. The throttle valve, a device located near the top of the combustion system that controls air intake, is particularly prone to carbon buildup due to its working environment and function. A common method for cleaning throttle valve carbon deposits involves removing the throttle valve, using a carburetor cleaner to wash both sides, and then wiping away the decomposed carbon deposits with a cloth.
I think engine carbon cleaning really depends on the specific situation. My car has been running for over five years, and recently I've clearly noticed some shaking at idle and sluggish throttle response. After consulting several experienced mechanics, they all said these are classic carbon deposit symptoms. With severe traffic congestion in cities nowadays, engines often operate at low RPMs, making them particularly prone to carbon buildup. If left untreated, not only will fuel consumption skyrocket over time, but the catalytic converter might even get ruined. During my last maintenance, we used walnut shell blasting for cleaning - when we opened it up, the intake pipe walls were completely covered with sludge-like carbon deposits. After cleaning, the throttle felt much more responsive. However, it's really unnecessary to do this during the first two years of a new car - that's just wasting money. Remember, the idea of using high-speed driving to remove carbon deposits is a scam - the engine temperature simply doesn't get high enough.
Having worked in auto repair for over a decade, I've seen it all. The backside of direct injection engine intake valves is particularly prone to carbon buildup, which over time becomes like a layer of concrete. Last week, a Tiguan had cold start issues, and upon disassembly, we found valve sticking caused by carbon deposits. Fuel additives only clean the injectors and have no effect on the intake tract. Walnut shell blasting gives the best cleaning results, but requires removing the intake manifold. Non-disassembly cleaning is suitable for those who don't want major work, but it's crucial to choose reputable brand cleaning solutions. The key is to change the engine oil afterward, as dissolved carbon deposits can contaminate the oil.
Three-year observation with Toyota hybrid: Carbon buildup depends on driving patterns. My highway-dominant usage keeps the engine at optimal conditions, with normal cylinder pressure readings during every maintenance. But my neighbor's city-driven Fit developed cold-start shuddering at just three years old. Even after replacing ignition coils, walnut blasting removed a teacup's worth of carbon deposits. He now uses fuel additives every two tanks and deliberately takes highway detours on weekends.
