Fuel system pressure, checking: Engagement
Engagement of fuel pressure gauge.
Supplement the pressure gauge with adapter and nipple before use.
Connect the adapter to the valve on the fuel rail in the locked position (box 1 in Fig 1, valve closed).
Set the cock on the pressure gauge in the direction of the nipple.
Connect the pressure gauge's other connection to the fuel drain equipment.
Unlock the adapter (box 2 in Fig 1, valve open).
Start the engine.
Read off the relative pressure.