Hi guys, time I introduced myself, and warn of what seems to me a fundamental FLAW.
I have driven this car with its N46B20 engine for almost 4 years and 28k miles and in almost all respects it is the best car I have owned in over 40 years driving. At 24k miles it uttered a grunt and the symbolic engine outline profile was displayed within the trapezium, all in yellow. The handbook told me I could continue with moderation, but have it checked without delay. I took it to a BMW specialist independent within 80m.
To cut a long story short, there was so much engine damage that I accepted the indie's recommendation to fit a scrapyard engine, at £5k cost. At 6 months out of warranty, BMWUK refused a goodwill contribution because it had been worked on by an independent. The independent swore it was defective manufacture. I was left with the bill
With unknown provenance, my car is not now worth very much.
IF THE SAME HAPPENS TO YOU, I ADVISE YOU TO IGNORE THE MANUAL, TREAT THE YELLOW LIGHT AS A RED, AND GET IT TAKEN ON A BREAKDOWN TRUCK TO SOMEBODY YOU CAN TRUST. Hope this helps somebody.