What was found
CAPT AND F/O UNRELIABLE AIRSPEED/ALTIMETER AND ENG LIGHT ON. AIR SPEED DISAGREE BY200 KTS CREW REPORTS CAPT AIRSPEED DROPPED TO 80KTS. EEC BITE FLT HISTORY SHOWS MSG 73-31641 & 73-31642 ADIRU TOTAL PRESSURE DISAGREE FLUSHED CAPT & F/O PITOT SYSTEM PER AMM 34-11-00. CHECKED PITOT PROBE HEAT & AOA VANES. NO DEFECTS. REPLACED CAPT AIR DATA MODULE PER AMM 34-21-04. CHECKED SYSTEM TO 300KTS & 10K FT ALTITUDE, OK ROTABLE PARTS CHANGE WAS INDICATED - TT 1418432 SN OFF 1354 MODULE, STANDBY OFF 42-3413-9-0001 1354 ON 29-3413-9-0001 2172.