So when I was driving home through the city from work yesterday my M5 started having serious hesitation problems when accelerating in 1st and 2nd gear, felt kind of like what I imagine a hairball feels like in a cat's throat, all constricted. I stepped on the accelerator a few more times and the car almost died, so I pulled over in a parking place fearing it wasnt going to make it home. I gave it a few revs up to about 3k or 4k and it sounded clear, so I proceeded on only to have the same hesitation for another block or so. Finally it cleared up and the car actually felt like it had smoother acceleration in every gear and was peppier. Is this normal? Does crap accumulate in the system that occasionally needs to get forced out like this? FYI, this car is my daily driver so does not sit around for days on end without being driven, for what that is worth.