just fixed (rigged) mine today thanx to reading this thread. Probably not perfect but at least my center vents blow cold air now. I didn't take the time to mess with the fresh air inlet vac lines. will save that for another day.

On an 85 300 td the vac pod (pink) is horizontally mounted right behind the center vents. the easy way to get to it (if you call it easy) is to remove the glove box. I also removed the passenger side center vent and vent boot to help access the pod. no need to mess with anything on the drivers side kick panel on this car.....

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83 TD wagon "Madge" PO's given name. 410k (150k engine)