Have you checked the routing of the poly V-belt? If not engaged with the tensioner, for example, it might be slipping on the turbo pulley.
Just an idea; hope it helps.
Ernie
Sssssorrrry! Didn't notice it was a diesel....thinking Kompressor on my car - at least I tried.
Ernie
I recently changed my power steering pump on my 2001 c220cdi mercedes but when i went to drive it i have no power it is like i have no turdo.. What have i done..