What is the function of an oil catch can?

[AubreyLynn]

The function of an oil catch can is to reduce the formation of carbon deposits. Below are detailed explanations about oil catch cans: 1. Principle: The oil catch can works by utilizing the negative pressure in the intake manifold to draw in blow-by gases formed in the crankcase, which are then redirected into the combustion chamber to participate in combustion again. These blow-by gases mainly consist of oil vapor and combustible gas mixtures. Since oil is viscous, if it directly enters the intake pipes, it may adhere to the inner walls of the intake pipes, potentially leading to carbon deposits and obstructing the intake. 2. Environmental protection: The engine has a Positive Crankcase Ventilation (PCV) system, which seems to only allow direct venting to the atmosphere. However, since the blow-by gases contain combustible gasoline molecules, releasing them directly into the atmosphere not only affects fuel economy but also causes more severe issues such as air pollution.