What was found
WHILE TAXIING, TOLD THAT A FLAME WAS COMING OUT OF THE NR 2 ENGINE. DECLARED AN EMERGENCY AND RETURNED TO THE GATE AFTER SECURING THE ENG. MAINTENANCE VISUALLY EXAMINED THE NR 2 ENGINE EXHAUST AREA AND FOUND OIL PUDDLE AND HEAVY SOOT INSIDE EXHAUST PLUG. IAW AMM 71-00 THIS CONDITION IS DESCRIBED AS A KIND OF CANDLE FIRE PHENOMENA. INSPECTED FLAME ARRESTOR WITH NTF, RAN ENG AT IDLE FOR 20 WITH NO FLAMES NOTED.