As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON CLIMB OUT #4 EGT GAUGE FAILED (ANALOG & DIGITAL) ALL ENG INDICTORS NORMAL. AFTER 40 MIN #4 EGT GUAGE STARTED WORKING AGAIN. *** CORRECTIVE ACTION *** FOUND EGT HARNESS CONNECTOR NOT PROPERLY SECURED ON #4 EGT INDICATOR. SECURED CONNECTOR ON #4 EGT INDIC ATOR. INSPECTED EGT PIGTAIL HARNESS ON #4 ENGINE. PERFORMED EGT INDICATOR TEST IAW DC-8MM 77-20-15  AND #5 EGT INDICATION GOOD.