What is this vacuum line behind my intake manifold?

[tutu10]

There’s a vacuum line with an unknown connection right behind my intake manifold. It’s located on the top side of a connector that extends from the wiring harness all the way across over to what appears is the second air pump. Does anyone know what this vacuum line connects to?

[9vapors]

Originally Posted by tutu10

There's a vacuum line with an unknown connection right behind my intake manifold. It's located on the top side of a connector that extends from the wiring harness all the way across over to what appears is the second air pump. Does anyone know what this vacuum line connects to?

Not sure what E70 you have... Sounds like you're referencing the vacuum canisters?

These are used to store vacuum pressure in case vacuum level drops due to major sea level fluctuations etc. The vacuum is used for a lot of things, wastegates, exhaust flappers, etc. the system is basically an overkill solution, most BMWs have 2 canisters and lots of folks delete 1 or both without issue.

I deleted one of mine because I hate the engine bay clutter.