As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING A PREFLIGHT RUN UP, THE GOVERNOR WOULD NOT CYCLE THE PROPELLER EVEN WHEN LT IN THE LOW RPM POSITION FOR 10+ SECONDS. THE PROPELLER GOVERNOR WAS REPLACED WITH SERVICEABLE & OPERATIONS WERE NORMAL. THE GOVERNOR ONLY HAD 29.5 HOURS SINCE OVERHAUL & THE REPAIR STATION WAS UNABLE TO DUPLICATE THE ISSUE WHEN THE GOVERNOR WAS RETURNED TO THEM. SUSPECT INTERMITTENT TEMP RELATED PROBLEM WITH GOVERNOR.