What was found
F/A REPORTS L1 REPORTS "STICKY" OR STICKING WHEN OPENING AND CLOSING. GROUNDED - YES. CLEANED AND LUBED GUIDE BLADE TRACKS. HEAR POPPING SOUND UPPER HINGE ON DOOR. FOUND GUIDE ARM TO BE WORN CAUSING POPPING AND STICKING. REMOVED L1 DOOR GUIDE ARM REF B737-800 AMM 52-11-21-400-802. INSTALLED NEW L1 GUIDE ARM WITH BOLT FASTENERS LOOSE REF AMM 52-11-21-400-802. COMPLETED INSTALLATION OF GUIDE ARM REF AMM 52-11-21. PERFORMED ADJUSTMENTS TO GUIDE ARM, HORIZONTAL CONTROL ROD ADJUSTMENT AND STOP PIN ADJUSTMENT REF AMM 52-11-00. OPS CHECK GOOD. REINSTALLED SLIDE PACK ASSY TO DOOR LINER REF AMM 25-66-01. FORWARD ENTRY DOOR SENSOR REF AMM 52-71-11 OPS CHECK GOOD.