As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MANUFACTURER DIAGNOSTICS REPORTED, NR 2 ENGINE TREND DATA SHOWS A SHIFT IN EGT HOT DAY MARGIN. ALL OTHER PARAMETERS NORMAL. EGT INDICATION ERRORS ARE SUSPECT. ACFT GROUNDED. FOUND NR 2 ENG HAD LOGGED FAULT CODE NR 77-20872 TOP LT EGT OUT OF RANGE, ON LAST 6 FLT LEGS. COMPLETED NR 2 ENGINE EGT CLEANING REF MM 77-21-00, REPLACED TOP LT (S4) T49.5 PROBE REF MM77-21-01. OPS CHECKED NORMAL,