You have an unmetered air leak that is causing the fuel starvation, the cis system requires the manifold to have a nice solid vacuum so the air sensing plate can react properly.

Otherwise you are going to have to test the distributor for supply issues, what you can do is to check the fuel inlet screen if its dirty.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)