I hope it is not the turbo as I am thinking about buying a used stock IX at the end of the week. Do not get me wrong, buying them used saves money but if the turbo is blown, I could spend that money elsewhere. I do hope the best for you. I do know that getting them rebuilt could be a pain. I know a guy that is pretty wise in the DSM scene about rebuilding turbos and he stands by his work. Shoot me a PM if you want his information.

Check your valves and valve seals.

It's probably turbo or install related. It's unlikely that you just happened to have a problem with something else at the same time you did the swap... Check every line while the car is running (under pressure) so you can be sure you don't have something simple causing the issue. Good luck.