As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTED LOSS OF MANIFOLD PRESSURE AND SLOW LOSS OF AIRSPEED. MADE A PRECAUTIONARY LANDING. INVESTIGATION REVEALED THAT THE EXHAUST MANIFOLD HAD BREACHED JUST BELOW THE NR 4 CYLINDER ALLOWING EXHAUST TO MELT THROUGH THE LT TURBO AIR INLET FILTER BOX AND MELT THE AIR FILTER.