As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AIRCRAFT TAXING BEHIND US REPORTED FLAMES COMING FROM TAIL PIPE ON NO.2 ENGINE, NO INDICATION IN FLIGHT DECK. INSPECTED #2 ENGINE INLET AND EXHAUST IAW FIM 71-05-00 NO DAMAGE NOTED. FLIGHT CREW RAN ENGINE AT IDLE ALL CHECKS NORMAL; OK FOR SERVICE IAW FIM 71-05-00.