W202 fresh air vacuum element
 

I've come to the conclusion that we have a leaky fresh air vacuum element. Has anyone done this before?

How can I identify which element it is while laying on my back under the dash?

What color vacuum line is it? My Haynes book doesn't have a vacuum diagram.

From the shop forum parts link I found:
http://catalog.eautopartscatalog.com/mercedesshop/sophio/quote.jsp?clientid=catalog.mercedesshop&cookieid=1YB1110PK1YB1115RE&baseurl=http://catalog.peachparts.com/&partner=mercedesshop&year=1995&product=O4010-99492&application=000444865

Which gives us this photo:
http://img.eautopartscatalog.com/live/O401099492BEH.JPG

I see two vacuum connections. Does anyone happen to know which is open and which is close? I'd be happy with fresh air all of the time and would like to just plug the vacuum line and wire the actuator open. If I ever have the dash out I'll replace the element, but I don't really want to remove the dash for just that one element.

-Tad

To replace that element yoy need to remove the dash.. at dealer we charged around 5.5-6 hrs.

Has 2 vacuum lines, a green/blue & a DARK red.

What problem are you having? There is a return spring on the actual fresh air flap that breaks and you will have a problem with the windows fogging up. The bottom line is that for either problem you have to remove the dash. The whole procedure is on the W202 CD available from MBUSA (P/N P-2700-202-03). It took me about the same time as M.B.DOC states.

A very high pitched noise every minute or so when the system is in the off position.

Thanks for the input,
Tad