As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RIGHT ENG BLEED SYSTEM HAS LARGE PRESSURE FLUCTUATIONS WITH ASSOCIATED ENG PARAMETER FLUCTUATIONS IN CLIMB AND IN CRUISE. WITH RIGHT PACK SELECTED -OFF- THE PRESSURE AND ENG PARAMETERS ARE STABLE. REPLACED ASCPC FOR RT AIR SUPPLY. ASCPC INSTALLED AND CABIN PRESS CONTROL SYSTEM TEST PASSED.