As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
INSTALLED OVERHAULED CARBURETOR AND RIGGED. WITHIN 10 HOURS, OWNER REPORTED ENGINE VERY ROUGH AT LOW POWER SETTINGS OR WOULD NOT EVEN IDLE. FOUND IDLE MIXTURE ADJUST SCREW GONE. NOTIFIED OVERHAULER WHO SENT NEW CARB. UPON INSTALLATION OF NEW UNIT, SPRING TENSION ON AJUST SCREW FOUND TO BE WEAK OR NON-EXISTANT AT CORRECT SETTING. OVERHAULER RECOMMENDED STRETCHING SPRING.