As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RETURNED TO ORD UNDER AMBER ALERT AND CANCELLED DUE TO NR 2 ENGINE FIRE WARNING. *S/D* AT THE TERMINAL ORD FOUND 13TH STAGE COOLING DUCT ON THE LEFT SIDE OF ENGINE AT THE 9 O''CLOCK POSITION FAILED. ADJACENT REVERSER BLANKET SECONDARY DAMAGE ON LEFT SIDE OF COWL. DUCT AND DAMAGED REVERSER BLANKETS WERE REPLACED. THIS ENGINE DISPLAYED ECM TREND PLOT SHIFT 3 FLIGHTS AFTER DUCT WAS REPLACED. ENGINE WAS REMOVED ON 3/30/00 DUE TO SUSPECTED HPT DISTORTION CAUSED BY LOSS OF COOLING AIR DUCT FAILURE.