As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR1 ENGINE FLUCTATED FROM 100 PERCENT TO 86 PERCENT N1 SEVERAL TIMES DURING CLIMB FROM FL 320 TO FL 380. ITT AND FUEL FLOW ALSO FOLLOWED THE FLUCTUATION. REPLACED NR1 FUEL FILTER WITH NEW, VERIFIED PRESSURE FROM EMERGENCY PUMP AT 20 PSI OPS & LEAK CHECKED GOOD IAW MM 73-20-21-001 & 28-20-00-01. ALSO CONFIRMED NO BLOCKAGE AT PT2 LINE FROM SENSOR TO FUEL COMPUTERS.