Hey 87 TII , with an s5 ht18s . i used to have a small gasket leak on the turbo manifold but now im noticing carbon buildup or deposits on my actual turbine blades, or the intake side . any ideas, nothing is loose

 

Deposits are totally normal on the turbine. Ideally it should be a tan or white, indicating that most of the time the car is burning around 14.7:1. Black and heavy carbon could indicate the car is running richer then it should.