I was trying to get this exhaust/turbo heat shield cover mounted properly so it doesn't rattle and discovered that the stud that goes on the intake manifold and also holds the turbo oil line in place was loose.
The tubular stud doesn't just go ON the manifold, it goes through it. The threads had stripped from vibration or over-torquing it and the hole had enlarged to about 2mm larger than the stud's threads. So pressurized air would leak out of there and also dirty air could be sucked in while at idle, possibly making the mixture leaner I'd suspect.
I used some hi-temp silicon to dress the stud up for now but I am wondering whether some metal epoxy paste would hold as a long term fix.

What material is the heat shield made off? I doubt that plain fiberglass would last the temperature of the turbo for this long. Maybe some hi-temp epoxy resin and kevlar?