I been hearing what sounded to be an exhaust leak close to my single turbo FD. After several checks I found no leaks on manifold of downpipe. I took it a step further and removed the UIM and found that my home-made block off plate that works at the top of the LIM had come loose. I am not sure of the name of the unit that was removed from that location but it used to sit just below the flange that mates the UIM to the LIM on the inner side by the secondary fuel rail. The area was very sooty which seemed to come from exhaust gas. Would this contribute to a slower spool?

 

ACV block off plate, likely not going to really affect much.