What was found
DURING TAKEOFF LEFT ENG SURGING POWER.POWER FLUCTUATION ON N1 FROM 85% TO 72%.POWER WAS TRENDING DOWNWARD.ONCE LEVELED OFF,POWER STABILIZED AT REDUCED THRUST OF 65% N1.DID NOT INCREASE POWER. OPS CHECKED THE N1 SPEED CONTROL AMPLIFIER DISABLE CHECK IAW CRJ-200 AMM 71-00-00-710-803. RAN IT FOR 15MIN AT 88.3 PERCENT N1 THEN TURNED SWITCHES ON AND RAN IT FOR ANOTHER 6 MIN AND COULD NOT DUPLICATE PROBLEM. OPS CHECKED GOOD AT THIS TIME