PCV Valve Operation:
A vacuum-controlled metering device that regulates the flow of crankcase fumes in the positive crankcase ventilation system by allowing more flow at high speed than at low speed, and acts as a system shutoff in case of engine backfire to prevent an explosion in the crankcase.
How To Instructions:
- Check for obvious problems.
- Give it an in-depth diagnosis.
- Out with the old, in with the new.