As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORD FLT 5933 THE CREW REPORTED 2 ENGINE SURGE FROM 35 PERCENT TO 75 PERCENT, ITT FLUCUATIONS BETWEEN 285 AND 777 DEGREES IN DESCENT WHEN POWER LEVERS BROUGHT BACK TO IDLE. SURGES ACCURED FOR APPROX 20-30 SECONDS. MAINTENANCE INSPECTED AND REPLACED THE NR 2 ENGINE FPMU. OPERATIONAL CHECKS WERE GOOD.