My Q5 (2.0 TFSI) was delivered recently and I have clocked about 310 miles on it so far. I took it out for a long distance drive today and noticed some erratic engine behaviour. At a constant speed of about 80-90 mph, I could feel the car surge a bit and the rev meter would fluctuate slightly. At that speed the engine is running at about 3000 rpm or so. I give it some gas and it goes away. Then after a couple of minutes of constant driving speed, the behaviour repeats itself.

I'm putting this down to the fact that mileage is still low, and the engine hasn't been fully run in yet. Anyone else can offer an explanation? I've only heard of engine speeds fluctuating at idle, but not when travelling at high speeds.