golf mk 3 engine problem

[bitofaboyraver]

hi, my uncle has a 1996 golf tdi cl. it has been sitting in his garage for a while and he has come to use it but cant. it had a few problems like the the pipe to the turbo had crack but he fixed that. it seemed to run ok cold but when its warm the engine starts to surge we have tried everything we can think of but we cant fix it:zx11: can you help:confused:
cheers