As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DIAGNOSTICS REPORTS NR 1 ENGINE TREND DATA SHOWS A SHIFT IN DELTA CRUISE AND TAKEOFF MARGIN INDICATIVE OF EGT INDICATION ERRORS. ACFT GROUNDED. R & R T49.5 (S4) PROBE IAW AMM 71-21-01. EEC BITE CHECKS GOOD IAW AMM 73-21-00-700-804-FOO.