Mb 312 D Loud tapping noise and loss of power
 

I have a Mercedes Sprinter 312 1999 312 turbo diesel, when the van was quite warm and under
load the engine start to tap quite loud.
When driving it will not go over 80kmph does not seem to rev more than 3000 rpm,
it also seems that the turbo is not kicking in.
I have changed the oil and used Liqui Moly to diesel purge to clean the pump and injectors.
Listening to the engine using a stethoscope the noise originates from the fuel pump or injectors.
While revving the engine the speedo needle also oscillates.
How can I check the diesel pump timing?
What does the adjustment screw on the pump adjust?
A person on the Benzworld.org site indicated that the problem lies with the fuel pump and that it could be fixed using advanced software.
He did however not indicate what software is required or where this software can be found.

The teenager at kiddyBenz is way over his head----don't start adjusting anything until you know the problem---the advanced software is MB's diagnostic software called DAS Xentry and you really need to find an Indy with that software and have the Sprinter authorization which will allow him to diagnose your Van!!

The alternative is going back to kiddyBenz for more mumbo jumbo aka Voodoo