So, I replaced the timing chain with a Febi Bilstein one, even though it didn't really need replaced. I also replaced the metal exhaust cam or rings with the newer rubbery ones. The metal ones looked slightly worn but not much.

I timed up the engine using my Laser tool and the timing is spot on. Guess what? The fault is still there, even after resetting the vanos adaptations.

Any suggestions? Anyone?

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