As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAH - FLT 3997 - THE CREW REPORTED A BURNING SMELL ORIGINATING FROM THE NR 1 BLEED AIR SYSTEM. MAINTENANCE REMOVED AND REPLACED THE NR 1 ENGINE IAW AIRCRAFT INSPECTION PROGRAM TASK CARD 6271001, REV 49, REF EMB-145 AMM 71-00-00. THE NR 1 AIRCONDITIONING PACK WAS REMOVED FROM MEL AND THE AIRCRAFT APPROVED FOR RETURN TO SERVICE. (M)