What Causes High Cylinder Pressure?
4 Answers
The reasons for high cylinder pressure: 1. Increased carbon deposits in the combustion chamber reduce the combustion chamber volume and increase the compression ratio, creating a false impression of high cylinder pressure. You can drive at high speeds a few times to utilize the high-speed airflow to clean the combustion chamber; 2. An overly rich air-fuel mixture in the combustion chamber or low engine temperature, poor exhaust flow, or a clogged catalytic converter can also lead to excessive cylinder pressure. High or low pressure in the cylinder directly affects the temperature at the end of compression. If the compression pressure is high, the temperature of the compressed air-fuel mixture or pure air will also be high, making the fuel easier to ignite with a spark plug (in gasoline engines) or self-ignite (in diesel engines).
I've encountered high cylinder pressure quite a few times. The most common cause is excessive carbon buildup in the combustion chamber. The carbon deposits act like plugs, occupying space and causing compression pressure to skyrocket. Another reason could be a blocked intake system, such as a clogged air filter or carbon-fouled throttle body, preventing fresh air from entering and naturally increasing pressure. Worn or stuck piston rings are also culprits – they fail to seal the cylinder properly, allowing compression gases to expand. Cooling system failures are related too, as engine overheating causes expansion and reduces cylinder wall clearance. Aftermarket modifications with excessively high compression ratios, like improperly adjusted turbocharger pressure, can also be to blame. For diagnosis, I use a pressure gauge to measure cylinder pressure or scan engine data. If it's high, immediate action is needed: clean carbon deposits, replace piston rings, or repair the cooling system. Otherwise, engine knocking or component damage may occur. For regular maintenance, using high-quality fuel and periodic cleaning are essential preventive measures.
Buddy, car enthusiasts all know that high cylinder pressure can be quite troublesome. It might be caused by carbon deposits accumulating in the combustion chamber, reducing space, or the intake pipe being clogged with dirt, restricting airflow. Worn-out piston rings getting stuck or incorrect modifications that increase the compression ratio are also common issues. I once encountered a case where the turbocharger pressure was too high, resulting in the engine making a cracking sound. The inspection method is simple—listen for idle noise or feel for sluggish acceleration during driving. For prevention, I’d recommend avoiding short trips to prevent condensation and carbon buildup, and using fuel additives for cleaning. Excessive cylinder pressure can lead to engine knocking, valve damage, or a sharp increase in fuel consumption, so regular engine health checks are crucial.
Once my car had abnormally high cylinder pressure which really scared me. The mechanic said the main issue was excessive carbon deposits occupying combustion chamber space, increasing compression pressure. Other causes included intake system blockages or piston ring wear; cooling system failures leading to engine overheating also contributed. The consequences could range from minor to severe - at best power loss, at worst catastrophic engine damage. I immediately went to the shop for carbon cleaning which fixed it. Car owners should prioritize regular maintenance and avoid engine overload.
