This ever recur for you? Same thing just happened to me in my 135i, at around 4900 on the odometer. I was on 101 as well -- maybe its the freeway.
Pulled off the road, shut it down, restarted and seemed to drive OK after that. Its at Sonnen now and I am expecting them to come back with the same looks ok, bring it in if it happens again response. Just wondering how yours has been holding up.