As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURNBACK L ENG SURGING AIRCRAFT YAWING N2 SURGING. CONTINUED WITH ENG RUNNING. LANDED ONT (+/- 10% N2 REPEATEDLY ON CLIMBOUT ) COMPLETED MPA TEST PER TASK 71-00-00-735-078-H03. OPS CHECK GOOD NO FAULTS NOTED AND NO SURGING DURNING RUN.