What is a PCV valve?

[DiLena]

Here is an introduction to the PCV valve: 1. Introduction: PCV is the abbreviation of Positive-Crankcase-Ventilation in English, which means the active ventilation control system for the crankcase (or oil pan) in Chinese. The PCV valve consists of a valve body, valve, valve cover, and spring, and cannot be disassembled. Its main function is to direct the gases inside the crankcase into the intake manifold through the PCV valve, with a small amount of air entering the intake manifold directly from the air filter via the PCV valve. This prevents icing at the throttle, incomplete combustion, and worsening emissions. It also prevents blow-by gases from entering the atmosphere and prevents engine oil from deteriorating. 2. Principle: The PCV valve is a metering control valve installed between the engine crankcase ventilation system and the intake system. The PCV valve is controlled by vacuum to regulate the flow of oil fumes from the crankcase ventilation system into the intake system. The flow rate is higher when the engine is running at high speeds compared to low speeds. Additionally, when engine backfire occurs, the PCV valve should cut off ventilation to prevent crankcase explosion.