I also have a 88 ranger 2.9 and I have a question for you. When you shut your engine off does the vacuum system, specifically the EGV make any noise? Mine does and so I bought a new one and it does the same thing only not so loud. I'm under the impression that it should not make any vacuum leaking noise.
Hope you can help me out. I have tried to get some response on the forum board with no luck.