Why does the engine have carbon deposits?

Carbon deposition is caused by incomplete combustion of combustible mixture in engine. Carbon deposition is harmful to the engine. Carbon deposition will affect the power of the engine and even lead to engine knocking. Knock is an abnormal combustion phenomenon of the engine, which occurs in the compression stroke.

The parts of the engine that are easy to deposit carbon are throttle, valve, combustion chamber and air intake.

If the throttle, valve and air intake are carbon-deposited, it will affect the air intake of the engine.

The air-fuel ratio will be inaccurate after the intake of the engine is affected, which will affect the power and fuel economy of the engine.

If carbon deposits appear in the combustion chamber, the compression ratio of the combustion chamber will increase, leading to engine knocking.

When the engine is in the compression stroke, the intake valve and exhaust valve of the engine will be closed, and the piston will run upward to compress the combustible mixture.

The temperature and pressure of the compressed combustible mixture will rise.

If the compression ratio of combustion chamber becomes larger, the temperature and pressure of combustible mixture will be higher than normal, which will lead to premature combustion of combustible mixture.

The combustible mixture will push the piston downward, and the piston will run upward at this time, which will affect the power output and fuel economy of the engine.

Severe knocking may even lead to engine piston cracking or connecting rod deformation.