What was found
DURING FLIGHT 3230, LT PROP OIL TEMP GUAGE IS FLUCTUATING BETWEEN NORMAL AND FULL HOT WITH TORQUE AT 60 PERCENT AND HIGHER SETTINGS. ALL OTHER INDICATIONS ARE NORMAL. AIR RETURN TO MEM. MAINTENANCE OHMED OUT WIRE TO WHITE HARNESS AT PGB OIL TEMP SENSOR, FIRE WALL AND WING ROOT. WIGGLED WIRES, ALL CHECKS GOOD. CLEANED CONNECTOR AT PGB OIL TEMP SENSOR REMOVED AND REPLACED LT PGB PRESS/TEMP INDICATOR IAW AMM 79-30=15-2 P/N 523535, S/N OFF 9803696A, S/N ON 221. RAN AC FOR 30 MINUTES VERY SLIGHT MOVEMENT IN NEEDLE, ALWAYS IN GREEN.