Carbon build-up has many names and many hiding places in your engine. It can be flaky, it can be virtually hard as a rock, and everything in between. Call it what you want--soot, gum, tar, glaze, varnish, lacquer, sludge--but it is always robs you of power, perfomance, and engine life.
In the air intake and intake valve areas of gasoline or diesel engines, it can be a flaky soot, which can break loose fairly eaily and cause big problems--especially true with newer Gasoline Direct Injection (GDI) engines. On your piston rings and in the rest of your crankcase, it can be a thich sludge, the consistancy of roofing tar, affecting compression. On your diesel cylinder walls, it is a hard glaze, caused by unburned fuel during idling. On your cylinder heads, it can be an almost rock-hard lacquer. Your exhaust and catalytic converter are always prone to carbon build-up, as are your all-important fuel injectors. And, in your automatic transmission, it is a sticky gum often causing shifting problems.
The vast majority of drivers are completely unaware of the formation of any of these carbon deposits or their effects on the life of their engines. Or, that there are affordable Do-It-Yourself ways to combat each and every one of the above mentioned soot's sneaky strongholds.
Share a carbon problem you are finding particularly intractable below in the comments
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