As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DUCT SPLIT ON CLIMBOUT. CLIMBING THROUGH FL360 RT SIDE 20 PSI LT SIDE 42 PSI. N1'S 100.9 N2'S 97.1 OAT 49C. DURING THE HEALTH CHECK THE HIGH STAGE REGULATOR FAILED THE OVERPRESSURE FUNCTION AND BACKFLOW TESTS. REPLACED NR 2 ENG HIGH STAGE REGULATOR PER MM 36 11 07. TESTED AND LEAK CHECKED GOOD. ACCOMPLISHED REPAIR CONFIRMATION IAW FIM 36 10 00 810 807 PARA G, OPS NORMAL.