I have been troubleshooting issues with loss of boost on my 1992 300D. After a few minutes of driving the boost turns off and restarting the car clears up the issues but only temporarily. The EGR valve was 100% restricted but there was no change after cleaning everything up.

In trying to set the Vacuum Control Flap i am running into some issues. Can anyone tell me the correct behavior of the vacuum unit on the control flap (part 100 in diagram) and MB part number 603 090 10 66

I assume it is most likely bad since i am barely able to pull more than 5 hg in on the mityvac when it looks like it should be set at 11 hg in. Or am i way off in trying to get this set?

I have not been able to find much information about this. Should it slowly leak vacuum? I can not get the valve to fully close with the mity vac, is this normal?

Thanks in advance for any advice, opinions or entertaining insults.

-todd