What was found
CREW COMMENTS: DURING CLIMB L 11PSI AND R 36PSI. IN CRUISE L15PSI AND R 25PSI. NEED TO CHK ALL MUSCLE LINES TO HPSOV, HPSOVC, PRV, PRVC, FAMV ON NR 1 ENG FOR LEAKS. CHECKED ALL MUSCLE LINES. NO LEAKS FOUND. REPLACED PRV CONTROLLER PER MM. DECAY CHECK ON NR 1 ENG FAN AIR TEMPERATURE SENSOR LINES CHECKED GOOD, NO LEAKS. REPLACED NR 1 FATS, OPS CKD GOOD ON HI-PWR ENG RUN TKO 4 MINS NO SPLIT, BLD SHIFT NML GOING UP & DWN , NO FAULTS.