Can anbody help? Turbo? T4 AVC 2.5tdi 2001

[alopotimus]

My t4 2.5tdi has been driving spot on until yesterday.
Its the AVC 2.5tdi 2001.
engine still normal except the turbo has seemed to stop working? cant hear it working although i can still hear a faint whistle or hiss?? normally between 2000 and 3000 revs the engine really pulls, but now its just like driving a non turbo van? is there a common fault on the turbo's? i can see it costing me a fortune if i have to replace the turbo ? can anybody help. Thanks

[kenney]

Hi,the fact that you hear a hissing suggests there is a leakage somewere,check all the hoses.

[alopotimus]

thanks i will check hoses, its only a very very faint noise. maybe intercooler sound? dont know alot about turbos / intercoolers

Its like the turbos just packed in. van still drives like normal, but without the turbo kicking in... is this safe to drive? or will it cause more damage?