A: The PCV valve is screwed into the manifold or pulled out of the camshaft cover in order to check it. The models with sequential multiport fuel injection have their camshaft covers connected to air intake plenum via a PCV hose. Threaded in the camshaft cover is where the PCV valve is fitted. When checking for vacuum unscrew it from the manifold or pull it out of the camshaft cover, start the engine and block the open end of the valve with your finger while idling at that point. If there's no vacuum, change the PCV valve. Disconnecting this hose involves loosening clamps securing it to both sides of the system: on one side it is clamped to a PCV valve and on another side-a camshaft cover. Remove its valve by unscrewing it from an intake manifold or pulling it out from a camshaft cover. Before buying another, ensure you are getting the right PCV valve for your car; compare your old one to confirm they match up. Threading into a manifold and connecting a hose to this part is what one does on carbureted models and those with throttle body injection. For models with sequential multiport fuel injection, attach a hose clamp over its grommet that has been forced through its hole in order to secure it tightly around both elements.