If anyone has an FSI with a slight hesitation when accelerating from lower RPM I may have found the problem by accident. I purchased my FSI about 5 years ago and as normal I have had a lot of frustration with it culminating in have a replacement engine at WOM,but even after that I still had this annoying hesitation. I thought it must the high pressure fuel pump as that was the same unit on both engines.Until about a month ago when I was filling with Tesco Momentum and the wind blew my fuel cap under the car because the rubber tether strap had broken about a month before. So I got straight on to Amazon and ordered a new fuel cap with tether for £7 It arrived next day. But when drove to work that evening the hesitation had gone completely and has not returned.Has anyone else found this cure?May work on other engine's?