As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING FLIGHT PILOT REPORTS "BURNING ODOR IN CABIN" MAINTENANCE INSPECTED ENGINE AND AIRFRAME FOR SOURCE OF SMELL AND NO CONCLUSIVE CAUSE COULD BE FOUND. IT IS SUSPECTED THAT DEICE FLUID MAY HAVE BEEN THE SOURCE OF SMELL. AN ENGINE COMPRESSOR TURBINE WASH WAS CONDUCTED AND GROUND RUN WAS PERFORMED WITH NO SMELL NOTED.