As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING NR 2 ENG BLEED AIR OPERATION CHECK, SMOKE NOTICED IN THE CABIN WITH STRONG ODOR. RAN ENGS FOR 30 MINUTES AT 90 PERCENT IAW GHC-10-13 WITH AIR GND CBS PULLED, NO ODOR NOTED. SUSPECT THAT THE SMELL WAS FROM THE NEWLY INSTALLED BLEED AIR O RINGS. NIGHT SHIFT TURNOVER STATED THAT THE SMELL DISSIPATED BEFORE ENG RUNS WERE COMPLETED BY THEM LAST NIGHT. OPERATIONS CHECKED GOOD.