As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDIS 638 21-01 1682341 21SEP18 PHL CLOSE WHILE STARTING EITHER #1 OR #2 ENG OFF APU, FUMES ARE PRESENT THROUGHOUT A/C. APU TEMP SPIKES TO MID 600 DEGREES 21585 00 EK HISTORY: . FACT 21SEP18 18:07 PHL WHILE STARTING ENGS OFF OF APU IAW PIEDMONT MAINTENANCE OPERATING MANUAL, NO FUMES IN A/C ARE OBSERVED. OK FOR SERVICE