So, at home again and cleaned the turbo with oven-cleaner, let it soke for approx 1½ hour before putting all together again. Unfortunatenatly theres absolutely 0 difference pre/post :-(
As this problem happended after cambelt broke (no damage done, was at idle & alternator-belt that jumped off & was eaten by timingbelt-wheel on crankshaft), somebody suggested that the timing could was off.
I have re-checked with markings on the belt & crank/camshafts which align perfect. My thought now would be to put the lockingtool on/into camshaft & then measure if cyl 1 is at TDC.
Could there be any problem in removing the glowplug instead of injector to do this measurement ?
Any other suggestion as to why i lack power down low? EGR is blanked of by plate.