I have had my S3 for 2 weeks now. It is a very well looked after car but I am having a few issues with it. The car was at stage 2 previously but the previous owner re set the REVO map to zero with the SPS controller as he stripped the exhaust etc from the car. I noticed a few flat spots early on but put this down to the map. The problem has got a lot worse now though. I fitted the ITG Maxogen kit to the car at the weekend and it was fine at first but the misfire/flat spots have got a lot worse. I have checked the kit and it is all secure. The previous owner said he fitted new cooler running plugs as recommended for stage 2 and these are still in. I will be getting a new Milltek and SPS controller and re setting the map shortly so I am hoping that solves the issues. Just a bit worried its a deeper lying problem and thought I would check and see if people have suffered similar issues before I start investigating Car is in Audi next week for service so I will get them to have a look at it as well. The problem is intermittent, it also struggles to start when cold so I thought it was a problem with the plugs.