As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LT DUCT PRESS FLUCTUATES BETWEEN 10 AND 60 PSI ON TAXI. PACKS ON, SMOOTHES OUT WHEN T/O POWER APPLLIED. REMOVED AND REPLACED PRSOV ON NR 1 ENG IAW MM AND SECURED SENSE LINE FOR THE PRSOV. PERFORMED ADJ AND TEST IAW MM. OPS CHECK NORMAL. (K)