What was found
APU TREND DATA SHOWS CT5ATP TEMP IS ABOVE 605 BUT BELOW THE THRESHOLD 632 DEGREES. ETOPS SIGNIFICANT SYSTEM TASK AFFECTS APU ON DEMAND IN-FLIGHT START CAPABILITY. THIS APU HAS BEEN PLACED ON ASA MEL 49-99B. CONTINUOUS OPERATION ON ETOPS FLIGHTS. GROUNDED - YES. REMOVED AND REPLACED 9 APU FUEL NOZZLES REF B737-900 AMM 49-31-14. COMPLETED STEPS E.2 TO E.3 REF B737-900 FIM 49-15 TASK 807. REPLACE 10TH FUEL NOZZLE REF AMM 49-31-14. LEAK & OPS CHECKED GOOD. NO VIBRATIONS NOTED DURING APU OPERATION REF FIM 49-15 TASK 807 STEP D.(1)