As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LIGHT BURN SMELL AFTER TAKE OFF, MADE FA2 EYES WATERING AND DISSIPATED QUICKLY. SMELL CAME BACK ON GROUND AFTER WE STARTED THE APU.-C/A-DEFFERED PACK 2 DUE TO COKED ACM PER MEL 21-44 AUTH# 040005D-C. FOUND PACK 2 HEAT EXCHANGER COKED WITH COFFEE/SODA PERFORMED DUAL HEAT EXCHANGER CLEANING IAW EO # EJ-2100-006 WORK CARD, PERFORMED OPERATIONAL TEST IAW AMM 21-51-00-710-801-A OPS CHECK GOOD MEL RESTORED