As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING ENGINE START, SUCTION PRESSURE WAS READING ZERO, DURING FURTHER TROUBLESHOOTING, TECH FOUND THE ENGINE DRIVEN DRIVEN DRY AIR PUMP HAD A BROKEN SHAFT. PROBABLE CAUSE COULD BE FROM VIBRATION OR HARD START. NO RECOMMENDATION AT THIS TIME. (K)