I've recently purchased a 2004 3.0i and am wondering if anyone has been able to actually fix this problem? I've plugged in a scanner and it hasn't pulled any codes. The car drives perfectly with no issues other than a loud vibration at idle.

If I blip the throttle to 700 rpm (idles around 600 rpm) the vibration will instantly go away.

I'm stumped. I've checked the mounts and they are fine. Ideally, I'd like to just raise the idle by 50rpm. That would be the easiest solution. Does anyone know if the BMW scanner 1.4.0 can adjust idle?