The Positive Crankcase Ventilation (PCV) valve ought to be checked on a regular basis to scrutinize whether it is blocked or not since it is situated on the valve cover and attached to the intake manifold with a vacuum hose. To remove PCV valve, unplug the vacuum hose off the valve and then pull the valve off the rocker cover grommet. When the engine demonstrates low gas mileage and bad idle behavior in the event of a lack of an apparent reason, the PCV valve could be plugged and ought to be changed.