What types of gases does the PCV hose handle in the engine?

The engine is the heart of the car, and it generates power by burning a combustible mixture (usually a mixture of gasoline and air). In this process, the piston moves up and down in the cylinder, pushing the crankshaft to rotate, which in turn drives the car forward. However, due to the tiny gap between the piston ring and the cylinder wall, as well as the wear of the piston ring itself, part of the combustible mixture will escape into the crankcase during the compression and power strokes. In addition, the exhaust gas produced during the combustion process may also enter the crankcase through a similar path.
The gases gathered in the crankcase are mainly composed of two parts: combustible mixture This is a mixture of incompletely burned fuel and air, which enters the crankcase through the gap between the piston ring and the cylinder wall. If these gases are not treated, they will cause the oil to be diluted, which will affect the lubrication effect of the oil and the life of the engine. Exhaust gas These gases are direct products of the engine combustion process, including carbon dioxide, water vapor, nitrogen oxides, carbon monoxide, and incompletely burned hydrocarbons. If the harmful substances in the exhaust gas are directly discharged into the atmosphere, they will pollute the environment.
In order to solve the problem of crankcase gas, engine designers introduced the PCV system. As an important part of this system, the PCV hose works by using the vacuum of the intake pipe to draw fresh air into the cylinder head cover (part of the crankcase) and mix it with the gas in the crankcase. Subsequently, these mixed gases enter the engine's intake pipe through the PCV valve (a one-way valve that allows gas to flow from the crankcase to the intake pipe, but prevents gas from flowing in the opposite direction) and the PCV hose, and finally enter the cylinder with fresh air for re-combustion.
The specific process of the PCV hose to handle gas, when the engine is running, negative pressure (vacuum) is generated in the intake pipe, which prompts fresh air to be sucked in through the vents on the cylinder head cover. Fresh air is mixed with the combustible mixture and exhaust gas in the crankcase in the cylinder head cover. The mixed gas is guided to the intake pipe through the PCV valve and PCV hose, and enters the cylinder with fresh air for combustion. Through this process, the harmful gases in the crankcase are effectively treated, reducing the emission of harmful emissions, while optimizing the combustion efficiency of the engine and ensuring smooth and clean operation of the engine.
The gases handled by the PCV hose in the engine are mainly the combustible mixture and exhaust gas escaping from the crankcase. By reintroducing these gases into the engine for combustion, the PCV hose not only helps reduce the emission of harmful emissions, but also optimizes the engine's combustion efficiency, extends the service life of the engine oil and the engine, and is a key component in the engine emission control system.