What was found
ELP - FLIGHT 4011 - DURING DESCENT THE CREW ATTEMPTED TO EXTEND THE FLIGHT SPOILERS. FELT A ROCKING MOTION AS IF THE SPOILERS MAY HAVE INITIALLY EXTENDED ASYMMETRICALLY. THE O/B SPOILERONS AND THE O/B FLT SPOILERS CAUTION MESSAGES APPEARED. THE INBOARD SPOILERS WORKED OK AND UPON LANDING, THE GROUND SPOILERS WORKED NORMALLY. MAINTENANCE INSPECTED THE AIRCRAFT AND REPLACED THE LEFT OUTBOARD MULTI FUNCTION SPOILER PCU. THE OPERATIONAL AND LEAK CHECKS WERE GOOD AND THE AIRCRAFT WAS RETURNED TO SERVICE.