What was found
CAPT PFD SHOWS SPD AND ALT FLAGS INTERMITTENTLY CREW REPORTS FLAGS APPEARED INTERMITTENTLY AT CRUISE. AT AROUND 1000 FT SYSTEM RETURNED TO NORMAL. PERFORMED FIM 34-21 TASK 839, PERFORMED INITIAL EVALUATION NO FAULT FOUND, ALSO CHECK FOR FAULTS ON ADIRU REF ADIRS BITE PROCEDURE, 34-21 TASK 801. NO CURRENT FAULTS FOUND. IF THE MAINTENANCE MESSAGE NOT FOUND THEN THERE WAS AN INTERMITTENT FAULT. A/C OK TO CONTINUE