Is there a way to replace the PCV diaphragm and valve without pulling the plastic valve cover? The PCV valve seems to be stuck open, very crazy idle surging, and I'd like to replace the valve. I see the little clips around the circular disk but I'm not sure if those clips will necessarily pry out. The alternative I can think of is to pull the valve cover and try to knock out the valve from the backside. Any ideas? Thanks guys.