As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 1 ENGINE HAS REOCCURRING REPORTS OF FAULT MESSAGE 73-31371 BEING SET. INDICATION SYSTEM TROUBLE-SHOOTING HAS BEEN PREVIOUSLY ACCOMPLISHED. ETOPS SIGNIFICANT SYSTEM EC/TC PWRL-73CMPT-07267-2. GROUNDED - YES. REMOVED & REPLACED NR 1 ENGINE UPPER ELEVEN FUEL NOZZLES PER PWRPL-73CMPT-07267-2. GROUND VERIFICATION REPAIR CONFIRMATION SUCCESSFUL, NR 1 ENGINE SATISFIES B737-800 FIM 73-11 TASK 801 CRITERIA.