As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, NR 4 ENGINE EGT AT REDUCED THRUST OF 1.40, CLIMBED INTO YELLOW FOR APPROXIMATE 2 SECONDS, THEN CLIMBS THRUST SET, REMAINED NORMAL AFTER TAKEOFF. NR 4 ENGINE NACELLE FIRE LOOP "B" FLUCTUATED (7-9) INTO RED WITH FAULT LIGHT FLICKERING AND "A" LOOP FLUCTUATING (3-7) IN YELLOW. FIRE DETECTION ANNUNCIATOR ON FORWARD PANEL ILLUMINATED. NR 4 ENGINE SECURED IAW QRH.