patallen

my E60 is making a very strange problem.
at cruising speeds, anything over 40mph, the car seems to have fluctuating power, could be felt as a random missfire but its not ( i do have icar soft and inpa). it feels like it gains/loose power at a constant pace, probably 2-3 times per seconds.
no code, no cel.
Very slight but annoying enough to investigate.

what i found very strange is that when i put the car on the cruise control, it doesnt do it anymore. perfect constant speed, no surge or hesitation or fluctuation.

wtf ?
pedal sensor assembly maybe ?

thanks for any ideas.