I've listened in that area but it sounds as if it is coming from the front of the engine (around the vac pump). This is why I am assuming the vac pump is defective but it still holds a vacuum. I was just wondering if anybody else may have heard something like this in thier's. It also takes a few seconds after the engine is off before it starts to whistle (kinda like someone holding a ballon and letting air escape while stretching the inlet).