As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING DESCENT, AIRCRAFT EXPERIENCED VIBRATION FROM RT ENGINE THAT LASTED FOR 5 TO 10 SECONDS AND OCCURRED SEVERAL TIMES. TGT ROSE INTO YELLOW BAND. ENGINE WAS PLACED AT IDLE UNTIL LANDING. REPLACED ENGINE AIRFLOW CONTROL RPM SIGNAL TRANSMITTER.