i actually found this by testing with carb cleaner. that area was the only place that raised the idle when carb cleaner was sprayed. eventually i determined it to be that nipple and not other hoses in the area. i tried covering it and it did improve the idle. but, i've still got something else bad going on with this oily plug and cylinder. i should be able to get it to my mechanic this weekend for diagnosis. i'll keep everyone posted.
86' 190e 2.3L 16v