As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING FLIGHT 3674/3411, NR 4 ENGINE TEMP 613 DEGREES, NG, 7 PERCENT BELOW OTHERS ENGINE. AIR RETURN TO MSP. MAINTENANCE REMOVED AND REPLACED NR 4 ENGINE BLEED BAND REF EO A72023 FOR DETAILS (P/N 2-161-182-18) (S/N ON 03246371277) (P/N OFF 2-161-182-01) (S/N OFF UNK). OPS CHECK GOOD .