My wife's 1985 300d has a leaky vacuum pod somewhere in the dash. Last winter she was having issues with hard downshifts when slowing down for a stop. I checked the vac supply to the trans and found it dropped significantly with any setting on the CCU turned on. I disconnected the green vac line to CCU and the vac readings were back up and the shifting was improved. The major downside was no heat on your feet all winter. With the cold weather coming up here in New England she wants good downshifts and heat on her feet this winter.

So, I'm looking for a way to figure out which pod or pods are leaking in the dash. I know the vac manifold is behind the CCU but what is the methodology for figuring out which pod or pods are bad?

Thanks for all your help!

__________________
-Louis
The Hills of Western Mass.
1985 300TD 327,777 sold to JB3
1985 300D 218,xxx
1987 190D 5 speed 338,xxx

Using the info in this thread: http://www.peachparts.com/shopforum/diesel-discussion/190425-climate-control-issues-1985-300d.html
I determined that it is my center vent and recirculating air flap (#3 and #5)
pods that do not hold vacuum.
For the time being I left the #3 and #5 switchover valves unplugged to bypass these pods. Is there any reason not to do this?
The car shuts off and I have heat on the feet. So far so good!

__________________
-Louis
The Hills of Western Mass.
1985 300TD 327,777 sold to JB3
1985 300D 218,xxx
1987 190D 5 speed 338,xxx