As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NOTED THAT THE FUEL INJECTOR SERVO WOULD NOT HOLD AN IDLE MIXTURE SETTING. MIXTURE SETTING WOULD NEED TO BE ADJUSTED FREQUENTLY. MIXTURE SETTING WAS NOTED TO CHANGE FROM BEGINNING TO END OF A FLIGHT. MIXTURE CONTROL SETTING KNOB ON THE FUEL INJECTOR SERVO WOULD ALWAYS REMAIN WHERE IT WAS SET, HOWEVER, ACTUAL FUEL DELIVERY WOULD BE INCONSISTENT DUE TO A SUSPECTED INTERNAL COMPONENT FAILURE OF THE FUEL INJECTOR SERVO.