2010 135i with 80k.
The car is 2010,an automatic, and if I am in, for example, third gear at 40 MPH and I just use the engine to accelerate to 60 (no downshift), the power delivery will stutter. It feels like slipping (but RPMs are not rising) so it must be something cutting out in the power delivery. I shut off traction control to rule that out, and it still stutters. I should add that the car starts and runs perfectly EXCEPT for the surging/stuttering at 3,000-4,500 RPM.
Ideas? I tried search, but the terminology is hard to match, and there are so many types of misses and stutters that are different.