Just tinkering around under the hood today and heard a noise I had never heard before. Took me a few minutes to track it down. Sounded almost like a bearing noise but on top of the engine. After feeling around I grabbed the pcv hose and it was shaking. Sounded like someone was rattling the valve also. Pulled the valve out of valve cover no change. Put my finger over pcv and had suction. Removed valve from hose and engine idled up but ran very smooth. I cleaned the old pcv out with some Wearever brake and parts cleaner and put it back in. Engine idled down, didn't run as smooth but no more shaking and rattling. Been doing this 25 years, never had this problem. Am I just dealing with a bad pcv valve or should I look for something else? By the way the valve was pretty nasty but I have seen much worse and it still moved freely. Any help???