Engine Room Puzzle Walkthrough — Valve Sequence & Pressure

The setup

The engine room is the one mandatory puzzle before the finale. You must restore pressure to the ballast pump so Sally can surface the sub. Three valves (red, blue, green) and two gauges must be balanced without tripping the alarm.

Valve sequence

The correct order is painted as a riddle on the bulkhead:

1. Blue — bleed the coolant loop first.
2. Green — open the intake to the pump.
3. Red — only after both gauges read in the green band.

Opening Red too early spikes pressure and triggers the soft-lock the 1.0.3 patch fixed.

Pressure gauges

• Left gauge must sit between 40 and 60 PSI.
• Right gauge must sit between 20 and 35 PSI.
• If the right gauge climbs past 35, close Green for two seconds, then reopen.

Common mistakes

• Turning Red before Blue/Green → alarm.
• Holding Green open while the left gauge exceeds 60 → overpressure.
• Forgetting to close the coolant bleed after Blue → slow pressure leak that fails the timed segment.

After the sequence

Once both gauges hold in band for 8 seconds, the pump engages and Sally's line plays automatically. Save immediately — the next room is the conviction interview, and there is no checkpoint between them.