Theory Of Operation: Notes
The Positive Crankcase Ventilation system (PCV) flows fresh air into the engine crankcase to dilute the unburned hydrocarbons present and route them into the intake manifold where they are consumed during the combustion process.
The PCV valve controls or meters this flow of crankcase vapors during all modes of engine operation. Each PCV valve is sized for a specific application to provide a flow rate that will meet the engines needs during idle, high speed, and heavy load conditions. PCV valves are not interchangeable based on their external dimensions; they must meet the designed flow requirements. The PCV valve meters the vapor flow under all engine operating conditions.