As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT LANDED ON REMOTE LEASE SITE AND UPON LOWERING THE COLLECTIVE THE ENGINE DID AN UNCOMMANDED DECEL TO 75 PERCENT. PILOT ROLLED THROTTLE BACK TO IDLE AND TRIED TO ROLL THROTTLE BACK TO 100 PERCENT. ENGINE WOULD NOT RETURN PAST 75 PERCENT. MAINTENANCE WAS CALLED AND FUEL CONTROL WAS REPLACED.