What was found
LEFT ENG EGT INOP AT CRUISE, WORKED IN DECENT PASSING F180. PER CONVERSATION WITH THE CREW, AFTER 4 HRS INTO FLIGHT, BOTH NORMAL & STBY EGT SHOWED 23 DEGREES & GOING THROUGH FL180 WHILE DESCENDING THE INDICATIONS CAME BACK TO NORMAL & REMAINED NORMAL ON LANDING ALL THE WAY TO SHUTTING DOWN AT THE GATE. LT ENG IDLE GROUND RUN CARRIED OUT, EGT INDICATIONS ALL NORMAL.ACFT RETURNED TO SERVICE. FOUND COMPENSATING RESISTOR OUTSIDE OF TOLERANCE PER AMM 77-21-03-705-001-R00. ACCOMPLISHED FUP ON LP 8992594 & FOUND GREEN WIRES IN BETWEEN TC 16 AND TC 17 RESTING ON ENG CASE, ADJUSTED P-CLIPS TO IMPROVE CLEARANCE. REMOVED ENGINE PYLON DISCONNECT PLUG D1010P WITH REF TO WDM 71-51-22-1.1 AND EXAMINED CIRCUIT FROM PINS 6 & 7 TO EGT TERMINAL BLOCK 2. NO FAULTS FOUND. CONNECTOR IN GOOD CONDITION. CONTINUITY CHECK FROM PLUG TO TERMINAL BLOCK CHECKS GOOD. VISUALLY CHECKED CHROMEL/ALUMEL CABLES FROM THERMOCOUPLE AFT SECTION FORWARD TO EGT TERMINAL BLOCK 2 REF WDM 71-51-22-01.1, REMOVED COMPRESSOR FAIRING RT CTR/LOWER PANELS IAW AMM 72-03-01-024-007-R00 & ACCESSED TO INSPECT. NO CABLE DEFECTS FOUND. COMPRESSOR FAIRING RIGHT CTR/LOWER PANELS RE-INSTALLED. REMOVED AND REPLACED EGT COMPENSATING RESISTOR PER AMM 77-21-03-404-707-R00.