2000 BMW 750iL - lumpy idle

[BMWM5LOVER]

Hi everyone,
my J spec baby has developed a weird idle. I get no error codes. I get no hesitation or issues if the AC is on or if I blip the throttle or am driving normally, however, if the car is sitting at its idle line (of i imagine about 400rpm?) the car feels like it has a muscle car 'cam' ..its lumpy, it shakes the whole car...

Where does one start? Vacuum issues? Tune up? Sensors? Why are there no warning lights?
Any one with experience or knowledge, Thank you for your feedback.

[CPHES]

Mileage? Could be different things - bad mafs, leaking intake manifold gaskets. How has the purchase experience of a J spec car been?

[Timm]

This is what you need: