As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THESE AIRCRAFT HAVE AN UPPER AND LOWER FIREWALL CHANNEL AND THE UPPER ALMOST ALWAYS CRACKS BELOW THE ENGINE MOUNT BOLTS. THIS AIRCRAFT HAD BOTH THE LEFT AND RIGHT NACELLES UPPER FIREWALL CHANNELS CRACKED AND HAD TO BE REPLACED WITH NEW.