As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEAK DURING ENGINE START ON #1 ENGINE OF THE PILOT VERIFIED LEAK COMING FROM #1 ENGINE HPTACC VALVE DRAIN AFTER MAINTENANCE IDLE POWER LEAK REF B737-900 AMM 71-00-00-700-801-100. GROUNDED - YES. REMOVED AND REPLACED #1 ENG HPTACC REF B737-900 AMM 75-21-01OPS AND LEAK CHECK GOOD. NO FURTHER DEFECTS NOTED.