I have replaced 3 coolant pipes the last week and the last one that burst was the coolant return pipe from the turbo.
When I took the pipe off I noticed it was blocked at the banjo joint with brown stuff (looks like mud that got a bit hard). So I removed the turbo the weekend and found that the coolant lines in the turbo is blocked as well. What could this be? Head Gasket? Turbo?
I did notice quite a big crack in the turbo next to the wastegate.
The car did not overheat at some stage...