As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NUMEROUS EXHAUST HEADERS LEAKING EXCESS EXHAUST GASSES AT JOINTS TO MUFFLER. SUBMITTER STATED THE MANUFACTURER SHOULD SIZE THESE PARTS CLOSER ON ASSY TO PREVENT CONTAMINANTS AND HEAT FROM GOING ONTO SPARK PLUG AND LEADS, AND SURROUNDING ENGINE COMPARTMENT.