As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING ADVANCE OF THRUST FOR TAKEOFF, A STRONG BURNING ODOR ENTERED THE AIR SYSTEM. THE ODOR WAS PERSISTENT UNTIL THRUST REDUCTION. UPON DESCENT AND LANDING THE SMELL CAME BACK STRONGER. PERFORMED ENGINE RUN AND OPERATED BOTH PACKS. NO DEFECTS NOTED.