As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAXI IN, ENGINE WAS VIBRATING AND MIS-FIRING AT OR BELOW 1000 RPM. MX PERSONNEL DUPLICATED PROBLEM BY PLACING MAGNETO SWITCH ON RT MAG ONLY. RT MAGNETO WAS REMOVED TO DISCOVER COIL PRIMARY LEAD TO POINTS HAD BROKEN OFF. COIL LEAD WIRE HAD NOT BEEN CRIMPED PROPERLY SO WIRE HAD BROKEN OFF TERMINAL END CONNECTOR CAUSING LOSS OF COIL POWER TO PRIMARY CONTACT POINTS OF MAGNETO.