As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHEN THE APU WAS STARTED AND BLEED AIR IS ON THERE IS AN OILY MUSTY SMELL COMING FROM THE BLEED AIR. TURN BLEED AIR OFF AND IT DISIPATES. CAN NOTICE A VERY SLIGHT HAZE IN THE COCKPIT AS WELL AS THE SMELL. REPLACED APU. OPS CHECK GOOD. IAW CE-700 AMM 49-10-00. OSD; 1/29/2025