- Maybe your small vacuum hose is cracked and broken off, this is why you don't see it.

- I fixed my SAS system in my 1998 528i and wrote it below. You can find some useful info in that DIY:

DIY: Troubleshooting S.A.S. and How to Replace the Famous Fuse # 107! - Page 3 - Bimmerfest - BMW Forums

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1998 E39 528i 5sp MT
2006 E53 X5 3.0 6sp MT