Bogging - throttle

Then all of a sudden, major bogging, like the throttle cutting in and out like 6 or 7 times , jolting me around in my seat extremely vigorously , and I mean vigorously. I let go of the pedal to make it stop and then accelerate slightly heavier, and all seems well.
Car is at operating temperature.
Any idea of what this can be? It’s happened a few times .Certainly, when I go to dealership, Ill get the, uhm “ unable to replicate “response.Extended CPO warranty ends soon so I want to make certain it’s not something major.
Thanks for insight.
2016 E63


