Sorry, I know this is probably a bit late for your issue, but hopefully it will help someone. Sorry, but I lost the sheet with the volume info apparently. Hope this helps.

Pressure 1 (PSI) Pressure 2 (PSI) Pressure 3 (PSI)
Range Note Range Note Range Note
46 - 52 Y491 54 - 61 Y492 36 Y493
Y491: Fuel Pressure (PSI) with vacuum to fuel pressure regulator.
Y492: Fuel pressure (PSI) without vacuum to fuel pressure regulator.
Y493: Residual system pressure (PSI). Fuel pump pressure after 30 minutes, engine off.