As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU BLEED DOES NOT INCRS FOR ENG START. MAX BLEED PRESS 15 PSI. ENG MAX MOTOR 20PCT N2. WITH PACKS OFF, MOTORED ENG, REACHED 22 PERCENT N2, 20 PSI DUCT PRESSURE REACHED. REPLACED APU FLOW SENSING MODULE, NO HELP. REPLACED SURGE VALVE DUCT PRESS 32 PSI UNLOADED ENG MOTORED TO 25 PERCENT.