As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA - LEFT ENGINE POWER SURGE PLUS AND MINUS 20 TO 30 PERCENT REPORTED AFTER DEPARTURE. CREW SECURED LEFT ENGINE AND RETURNED TO STATION WITHOUT INCIDENT. MAINTENANCE REPLACED LEFT ENGINE FUEL CONTROL UNIT. ENGINE GROUND RUNS NORMAL. AIRCRAFT RETURNED TO SERVICE. (M)