B737-900
Maintenance Airframe; Maintenance Powerplant
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action
Aircraft; Procedure
Installed #2 engine PRSOV (Pressure Regulating Shut Off Valve) and on [the] following flight at station ZZZ; [the] high stage check valve was found disconnected. High stage valve is in general location of work performed but high stage check valve was never disturbed.
Technician reported discovering the #2 engine high stage valve disconnected when installing the Pressure Regulating Shut Off Valve.