As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 0673 PDX & MFR AIR TURN BACK & DISCREPANCY. NR 2 ENG PARAMETERS & POWER FLUCTUATED IN FLIGHT. CREW COMPLIED WITH QRH. DE-SELECTED NR 2 ENG CONTROL UNIT. RETURNED, NO EMER DECLARED. NUMBER 2 ENG CONTROL UNIT FAULT, ISSUE DEFERRED. DEFERRAL CLEARED BY REPLACING NR 2 ENG CONTROL UNIT. ENG TRIM COMPLIED WITH IAW JIC 73-23-61 OPT 10040-001. OPERATIONS & PERFORMANCE CHECKED GOOD.