The PCV valve an a 2000 Chevrolet S10 is seated in a small hole on the valve cover of the engine. There is a small rubber hose attached to a component protruding out of the cover. The hose is attached to the PCV valve.
A PCV (positive crankcase ventilation) valve is part of the emissions control system. Most modern vehicles have one on the valve cover of the engine.
The PCV valve is a metal or plastic cylindrical-shaped component with a connection for the small hose on the upper end of it. The valve is removed by gripping it with pliers and giving it a gentle tug upwards from the valve cover.
The PCV valve is a one-way valve that helps remove partially burned gasses from the inside of an engine's crankcase and sends them to the combustion chamber for ignition. This helps the engine run more efficiently and reduces exhaust emissions.
