One for the experts on vacuum systems!

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Originally Posted by bawareca

Since N62 is using no throttle body to control the engine load it has a mechanical vacuum pump and it is another downside of this engine.
But I digress. The vacuum is also used to control the turbo[s], so if there is a low vacuum or no at all there will be a problem with the boost control and it should be pretty noticeable.
Here is the vacuum control diagram

RealOEM.com - Online BMW Parts Catalog

I think my problem may be at the electrical switch at the end of hose 16. I disconnected both vac lines from this switch, and there is vac going into it (from hose 15) but nothing when I cover the nozzle of the switch that hose 16 goes over.

I might make a temp bypass of the switch by just connected the 2 hoses together and see if I get vac at the other end of hose 16 (the engine mount end). Any reason why this wouldn't work?