190hp/410nm jtd 8v
Join Date: Jan 2013
County: Noord Holland
Usually having a power surge at higher gear / higher rpm means that the the turbo is going out of range of your MAP sensor. i've had the issue as well, and we solved it by replacing the turbo pressure sensor on the back of the airbox. If that doesn't help, it could be that the vanes in the turbo, due to soot and other crappy deposits are not able to move anymore, or move to slowely making the turbo unable to adjust it's vanes in time and thus overboosting.
Could be EGR, but that's supposed to be closed on higher rpm's , unless it's stuck, but dont know if that should be able to cause power surges..