I know this is one of those things that is notoriously hard to diagnose but, Golf V5 with 20v AQN. When accelerating at any point in the rev range the car will pull for split second, then slow, then immediately start again. The throttle is also very very jumpy although as I understand this is just how the car is mapped. It also seems fairly easy to stall. After much messing around with throttle body calibration, ECU resets and removing the battery, I managed to get the car to drive much nicer for about 20 seconds. That was achieved my connecting the battery and driving off immediately. All the plugs have been replaced, MAF has been swapped too.