As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CAPTAIN REPORTED SMOKE IN THE CABIN AFTER ENGINE GATE START. TROUBLE SHOOTING CONFIRMED SMOKE IN THE CABIN WITH APU RUNNING. REPLACED APU ENGINE PER AMM 49-11-01. OPS CHECKED AND LEAK CHECKED GOOD. AC PACKS NEED OIL BURN OUT TO BE ACCOMPLISHED. ITEM ROLLED FORWARD. ACCOMPLISHED PACK BURN OUT. A/C RETURNED TO SERVICE. SUSPECT CRACKED OIL LINE DUE TO VIBRATION.