What was found
DURING TAXI ON SINGLE ENGINE THE LEFT GEN TRIPPED OFFLINE. A SINGLE RESET WAS ATTEMPTED PER QRH. GEN TRIPPED AGAIN AFTER 20 SECONDS. APU WAS STARTED AND CARRIED THE LOAD NORMALLY. LEFT ENG EEC C1 STATUS MESSAGE ALSO DISPLAYED. TRIED GCU NO HELP. DELTA P POPPED. REMOVED NR 1 ENGINE IDG PER M/M. INSTALLED NR 1 IDG PER M/M. RAN NR 1 ENGINE. CHANGED NR 1 IDG FILTER. NO DEBRIS FOUND. LEAK CHECK GOOD. OPS CHECK NORMAL.