As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DEN - FLT 432 - EN ROUTE DEN-DFW, AFTER TAKEOFF, THE LEFT ENGINE HAD WHAT APPEARED TO BE A PRESSURE STALL. THE ENGINE WAS SHUT DOWN AND THE AIRCRAFT RETURNED TO DEN WITHOUT INCIDENT. PERFORMED ENGINE BORESCOPE PER MM. REPLACED THE LEFT AND RIGHT HP3 SOLENOIDS, HP2 SOLENOID, LEFT AND RIGHT HP3 BLEED VALVES AND HP2 BLEED VALVE. SYSTEM GROUND CHECKED NORMAL OPERATION. (M)