Thank you for those .

I see #44 are the restrictors and #45 is the check valve .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

From what my sleuthing of my own car tells me, the foot flap and fresh air flap have external red bands (270 degrees of a full circle) that squish the flexible line.

In an ac evap replacement picture, the yellow check valve is clearly shown. Can’t quite discern if the restrictor is an external type or in line. I would guess in line since a 4 way rubber and 3 way rubber could be used to connect everything. I wouldn’t imagine a brand new type of connector being used.

It’s definitely interesting. The vacuum source for my center flap does a wierd loop type deal where it is stuffed into the cavity of the evap box. On this loop is a red restrictor.

I’m definitely making things way more complicated than necessary, but I’m curious as to the why now.

I don't think you're making it more complicated, the Engineers made it and once you understand how it works you can maintain it better .

I used to have a chart of the various restrictors size and matching colors with part numbers, IIRC there were five different .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better