As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW RETURN TO GATE WITH OXYGEN MASK DONNED DUE TO A DIRTY SOCK SMELL AFTER ENG START, STRONG IN CABIN. ISOLATED SOURCE TO NR 2 ENG IAW JOB CARD 26L00021001. FINDINGS LIMITED TO OVER SERVICE OF NR 2 ENG OIL TANK. CORRECTED SAME & ACCOMPLISHED ECS DECONTAMINATION IAW JOB CARD 26L00021004.