What was found
DESCENDING THROUGH 12000 FEET, THE APU OSS AT FLIGHT IDLE , FA'S SMELLED THE DIRTY SOCK ODOR AND FLT CREW NOTICIED IT IN THE COCKPIT. IT SEEMED TO OCCUR MOSTLY WHEN POWER GOES TO IDLE . EVERY TIME CREW REDUCED POWER TO IDLE GOT THE STRONGEST BLAST OF ODOR. FINDINGS FOR OIL ODOR IN CABIN ARE AS FOLLOWS (1)-ENGINE OIL CONSUMPTION FOR LAST 7 DAYS ENG NR 1-2.2 QTS ENGNR 2 -3.1 QTS (2)- ENGINE GEAR BOX DRAIN ENG NR 1-2.5 QTS ENG#2- 2.5 QTS (3)-ENGINE BOROSCOPE FOUND COKING ON #1 ENG AT 2.5 STAGE. AS PER POWERPLANT ENGINEERING, TECH SUPPORT AND IAE REP, RECOMMENDED FOR ENGINE WASH, PACK BURN AND THEN PACK OZONE FILTER CHANGES. ENGINE WILL HAVE DEFERRAL ASSIGNED TO CHECK THE 2.5 STAGE AND A LATER TIME. ENGINE #2 FOUND WITH NO ABNORMAL FINDINGS.