What was found
VERY STRONG ACID ELECTRICAL SMELL LIKE BURNING PLASTIC IN THE DESCENT STARTING AT FL180 REF AMM 71-00-00-795-034-H03 TEST NO. 3 - GROUND TEST - IDLE LEAK TEST. RAN ENGINES FOR 15 MINUTES WITH NO NOXIOUS ODOR NOTED AT THIS TIME WHILE ENGINE 2 SOLE SOURCE OF BLEED. PERFORMED THE REMOVAL OF CONTAMINATION FROM THE AIR CONDITIONING AND PNEUMATIC SYSTEMS, AMM TASK 21-00-21-102-030. AIRCRAFT OKAY FOR SERVICE AT THIS TIME.