As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING GROUND RUN-UP, THE LEFT ENGINE WOULD ONLY DEVELOP 89 PERCENT N1 (COMPRESSOR RPM). INSPECTION OF THE FUEL CONTROL P3 AIR LINES REVEALED A LOOSE B-NUT AT THE PROP GOVERNOR. LEAKAGE IN THIS LINE LIMITS THE FUEL CONTROL TO 80 PERCENT (MAXIMUM REVERSE N1). THE SAFETY WIRE FOR THE B-NUT HAD BROKEN AND ALLOW THE B-NUT TO LOOSEN. THERE IS NO REASON EVIDENT AS TO WHY THE SAFETY WIRE BROKE.