As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 2107 - EWR - FLIGHT CREW REPORTED BURNING SMELL FROM PACK NR 1 WITH ENGINE BLEED ON. EWR MX PERFORMED OPERATIONAL CHECK OF PACK NR 1 WITH APU RUNNING AND QITH ENGINE RUNNING BUT COULD NOT DUPLICATE THE BURNING SMELL. ACFT WAS APPROVED TO RETURN TO SERVICE.