What was found
AT CRUISE, DUCT PRESSURE RT-41, LT -23 PSI. AT DUCT PRESSURE STABILIZED RT-40, LT-39 PSI. ACFT GROUNDED. PERFORMED NR 1 ENGINE BLEED AIR SYS HEALTH CHECK REF AMM 36-00-00-860-807. FOUND HSV AND PCV VALVES OUT OF TOLERANCE. NR 1 ENG PCV R & R, PERFORMED INSTALLATION TEST AND CKD GOOD REF MM 36-12-02 AND LEAK CK GOOD. R & R HSV ON NR 1 ENG PERFORMED INSTALLATION TEST AND CHECKED GOOD, IAW AMM 36-11-06 AND LEAK CHECKED GOOD.