What was found
ON FLIGHT 3856, CREW REPORTED DURING DESCENT, PACKS PRODUCED ODD ODOR (POSSIBLY OIL) FOLLOWED BY PACK 2 OVERHEAT, AIRCRAFT REMOVED FROM SERVICE. PERFORMED VISUAL INSPECTION OF OIL LEAKAGE AND ALSO PERFORMED BOROSCOPE INSPECTION FOR OIL LEAKAGE. NO EVIDENCE OF OIL FOUND. GROUND RUN A/C AND NO ABNORMAL OIL SMELL DETECTED. AIRCRAFT RETURNED TO SERVICE.