What was found
DURING FLIGHT 3200 OUT OF DTW, LT PROP RPM FLUCTUATES AFTER T/O. LT PROP CYCLED 20-30 RPM WITH SYNC ON, TURNED PROP SYNC OFF, NO HELP. MOVE CONDITION LEVER, NO HELP. LT PROP OIL PSI=100 PSI AND OIL TEMP WAS IN GREEN ARC. AIR RETURN TO DTW. MAINTENANCE RAN LT ENGINE AT VARIOUS POWER SETTINGS NO FLUCTUATION LT PROP Z NOTED. PROP SYNC OPERATED NORMAL. NO DISCREPANCIES NOTED.