As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 1 ENG BLEED, RTFL. LEFT DUCT PRESS SHOWING 5 PSI IN CRUISE AFTER SURGING DURING CLIMB. LEFT ENG BLEED OFF LIGHT ON. ACCOMPLISHED MM, PNEUMATIC SYSTEM HEALTH CHECK, PRSOV FAILED CHECK. REPLACED PRSOV PER MM9, TESTED NORMAL DURING HIGH POWER ENG RUN.