Ok, I will try to log it when possible. I don't have an ecutek kit, I think it is expensive to buy one and I got my turbo etc.. done with a tuner.
This is a video if it helps at all. At 4.5k rpm you can see the rev limit I talk about. In this video, it only occurred for half a second but in other times, it occurred for longer as if there is a rev limiter there preventing me to rev higher.