I've recently 'adopted' a 1989 E350 van with the 7.5 EFI and on the back of the engine is a vacuum tree that seems to be missing a hose to it, (or perhaps a vacuum plug that came off?)

I can't find (yet) a disconnected vacuum line. I've searched around for a vacuum diagram for the motor but have not found one yet. (I do have a factory repair manual coming however)

Anyone have a link to a good schematic? I've plugged it and the motor runs but it runs way too rich at idle. I figure once I get the hoses right, that might clear up. .

 

I'm looking for name of the part the hose and nut that connects into the manifold. It runs from the map sensor but I haven't been able to find it anywhere online or at my local Ford parts dealer.