Another thread for another potential issue. As I understand it, this valve should open and close as the engine revs. However, it doesn't seem to move at all. I can open it manually while the car is idling, which causes the RPMs to drop. I took the video below to demonstrate. I took it off and cleaned it all over, and it seems to move smoothly (the spring holding it closed is pretty strong.) Am I missing something? Maybe this only moves once the engine is warmed up?
(Sorry for the vertical video.)