As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT DUCT SHOWING 5 PSI IN FLIGHT AT CRUISE. RECONNECTED SEPARATED LT ENGINE PNEUMATIC SUPPY DUCT, AND REPLACED SEAL UPSTREAM OF LOW AND HIGH PRESSURE "Y" MANIFOLD PER MM CH 36-11-01. LK & OPS-CK GOOD ON ENGINE MX RUN IAW MM CH 71-00-00 AND CH 36-00-00.