That's the prob with the cam sensor. They fail-ish. Add long as they sorta work you won't get an error related to the cps, the computer will prefer to believe the cam is going through wormholes to achieve the impossible rates of change rather than believe the cps can send data that gets faster and slower than reality.

It's still a guess and hope it's the correct one. Both our M54 needed new CPS about 130,000 miles. They had the symptoms of turning off the engine for you when you dropped throttle going slowly (like coming to the middle of intersection waiting to turn left or pulling into a parking space).

I bought a similarly advertised OEM part but from Amazon and I felt confident when the directions were in German. Ok paid a lot more, I think I'd maybe get one of those eBay gems just to have a spare. I would never buy a CPS not OE or OEM. (Eg local store)

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)