As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAH - FLT 968 - THE CREW REPORTED A BURNING SMELL FROM THE NR 1 AIR CONDITIONING PACK AT TAKEOFF THRUST. MAINTENANCE UNSTUCK THE NR 1 PACK VALVE, SATISFACTORILY RAN THE ENGINES ON THE GROUND AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE. (X)