I have just got my car back from Audi after they fitter cruise control for me and also checked the cam follower for wear. They also replaced a screw that had come out of the exhaust heat shield. Since I have got the car back I have noticed an ever so slight stutter in the power delivery at constant speeds, say for example motorway driving. It feels like I take my foot off the accelerator for a split second and then return it. The stutter is so slight that my passenger couldn't notice it but being the driver I could. I have never filled up with Tesco 99, always Shell V Power. I was driving on the motor way today watching my boost gauge to see the stutter. The car looses about 5psi for a split second and then regains it. And when giving it some it throttles back the boost for a little before returning it, feels like a dip in the torque curve. Does anyone know what this could be? It seems to happen at random points through the rev range. What could Audi have done when fitting the cruise control that made this stutter appear? Should I take the car back to Audi or to AmD? Many thanks for and help in advance!