What was found
APU FAILED TO START AFTER 3 ATTEMPTS, APU FAULT LIGHT DISPLAYED. PERFORMED ECU BITE IAW B767 FIM 49-11 F/T 987, NO FAULTS NOTED. RESET PER FIM, APU STARTS FIRST ATTEMPT IAW AMM 49-11-00. PACK AND ELECTRICAL LOAD NORMAL. APU INOP DUE TO AUTO SHUTDOWN. REMOVED AND REPLACED APU SURGE CONTROL VALVE IAW AMM 49-53-01. OPS CHECK NORMAL, NO LEAKS NOTED.