All the PCV valves for the four cylinder models are are usually situated on the valve cover while the V6 models , it is usually on the front valve cover. Instead, remove the hose, remove the PCV valve from the cover, then engage the hose back; there might be a foam rubber silencer over the PCV valve in some models, it has to be removed before doing anything else. As the engine is now warmed up, insert your finger over the valve opening and experience no vacuum; if the hoses and valves are plugged or have deteriorated then replace them. Once you shut off the machine, unscrew the PCV from the hose and blow through it at the valve cover end; if no air gets through, you should change to another valve. Make sure to get one that is right for your certain make and model of your car and your specific engine size and comparing the old valve to the new one to make sure they are one and the same.