It's most definitely a leak from the intake manifold.
the CLS doesn't even operate with the car running, all connections are good. I have gaskets on order, and I have a 126 vac pump. the locks are getting converted to electric, and the brake booster and the CCU will be fed by the same pump.
the only thing that will rely on real engine vacuum, will be the warm up and fuel related things and the modulation..Even that I'm thinking of adapting a VCV from a diesel to control the vac..I'll have a much broader adjustment with my modulation as well that way.

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RIP: 80 300SD
RIP: 79 450SEL
2002 E430 4matic (212,000km)
2002 ML500 'sport'

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