As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AT 350 HAVE PNEU DUCT SPLIT LEFT SIDE 17 PSI RT 35 PSI. TROUBLESHOT IN COMPLIANCE W/FIM 36-10 TASK 807/806, AMM 36-11-00-700-801, FOUND PRE-COOLER VALVE INOPERATIVE. REMOVED AND REPLACED PRE-COOLER CONTROL VALVE IAW AMM 36-12-02. OPS CHECKED NORMAL.