As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT HAD JUST RUN THE ENGINE UP TO FLIGHT IDLE IN PREPARATION FOR TAKEOFF WHEN THE ENGINE CHIP LIGHT ILLUMINATED. A LARGE CHIP .0937 INCH BY .0625 INCH WAS FOUND ON THE UPPER CHIP PLUG AND SUBSEQUENT INSPECTION FOUND 2 ROLLERS WITH DEEPLY SPALLED AREAS ON THE WORKING SURFACES.