How to: Inspect and Replace the PCV Valve

The positive crankcase ventilation (PCV) valve is a one-way valve that allows fumes and pressure from the engine to be drawn into the combustion chamber of the car and burned, reducing emissions.

If the PCV valve sticks closed, pressure and fuel will build up in the crankcase, and the gaskets and seals of the engine can fail. If it sticks wide open, the car will be pulling too much from the crankcase and the car probably won’t accelerate or run well at high speeds.



Replacement PCV valve (if needed)


1. Locate the PCV valve.

The PCV valve is usually on top of the engine, ...

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