As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
HOLE IN FIREWALL OBSERVED DURING ANNUAL INSPECTION. UPON REMOVAL, FOUND INTERIOR CORROSION MUCH MORE ADVANCED THAN EXTERIOR. HOLE SEEMED TO BE CAUSED BY CONSTANT EXPOSURE TO TURBOCHARGER OPERATING TEMPERATURES. PLASTIC ON AFT SIDE OF FIREWALL EXHIBITED SIGNS OF THERMAL BREAKDOWN AND CHARRING.