As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE PERFORMING T/C N8010004 SUBTASK 10-11-07-710-003, PER B737-900 AMM 21-00-05-780-801 STEP E PARA 5 ECS PACK ON/OFF LT PACK FLOW CONTROL SHUT OFF VALVE STAYS IN THE ON POSITION, INTERMITTENTLY WILL GO CLOSED. GROUNDED-YES. REMOVED AND REPLACED LEFT PACK FLOW CONTROL AND SHUTOFF VALVE, PER B737-900 AMM 21-51-01. OPERATIONS AND LEAK CHECK GOOD, REF T/C N8010004 FOR COMPLETION OF AMM TASK 21-00-05-780-801.