Mercedes Sprinter air intake manifold replacement repair vac problem P226300 boost pressure

my sprinter van was going in to limp mode and sounding like a vacuum cleaner, i run diagnostics and it was trowing up lots of different fault codes. but the main one that keeps coming up is P226300 - The boost pressure deviates from the specified value.
the problem that i have found ,is that the bolts that hold the air intake manifold on shear off ,and there is no longer a sealed system ,there was the lack of turbo at first and the engine management light on ,and then the noise like sucking air and when i looked up from under the engine i could see the oil leaking from around that area. so i was pretty convinced this was going to be the problem i wanted to put up some information on this as i could not find any think that was helpful
hope this helps someone thanks for watching