Had a strange problem earlier;
The car was doing high speeds (legal of course) and when I let go of the rev and pressed the brakes it sounded as if the engine was in neutral, I then let go and it was ok, re-applied the brakes and it sounded like it was in neutral again. On the screen it showed Sport (S) and in 6th gear.
This problem went away when I tried it again 30 minutes later.
The car does randomly rev to 1-1.1k when idle then settles down.
My mind is telling me the mechatronics but could it be the engine too?