As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING ENGINE PERFORMANCE GROUND RUN AFTER INSPECTION, ENGINE WAS RUNNING ROUGH. ENGINE COMPRESSION CHECK CARRIED OUT AND CYLINDER NR 3 FAILED COMPRESSION CHECK AND AIR WAS LEAKING FROM THE EXHAUST. ROUGH RUNNING DURING TAKEOFF WAS ALSO REPORTED BY PILOT PREVIOUSLY WHICH COULD NOT BE CONFIRMED DURING GROUND-RUN AT THAT TIME AND AIRCRAFT WAS TEST FLOWN SATISFACTORY. (TC NR 20070114001)