What was found
AIRCRAFT WAS GROUNDED. ON APPROACH AT DFW AIRCRAFT INTERCEPTED GLIDESLOPE WITH CONG 2 170 KNOTS AIRCRAFT HAS UNCOMMENDED AIRSPEED INCREASE TO 195 KTS AND LOWERING LANDING GEAR HAD LITTLE EFFECT ON SPEED AFTER GO AROUND ON SECOND APPROACH AIRCRAFT RESPONDED THE SAME ONCE INTERCEPTION GLIDESLOPE, AUTO THRUST AND AUTOPILOT WERE DISCONNECTED AND WITH THRUST AT IDLE (28% N) SPEED SLOWLY CAME BACK BE STABLE AT 500 FEET AND LAND. ACCOMPLISHED TSM TASK 22-61-00-810-80-2A. NO DISCREPANCIES NOTED. REMOVED AND REPLACED FAC 2 PRECAUTIONARY, PER AMM 22-66-34. AFS AND LAND CAT 3 TEST NORMAL.