When the fuel pressure of the commonrail becomes higher than the target injection pressure, the pressure discharge valve receives a signal from engine ECU, in order to open the valve and send fuel back to the fuel tank so that the fuel pressure can return to the target injection pressure.
1. At target fuel pressure (common-rail or injection pressure)
2. Over target fuel pressure (commonrail or injection pressure)
HINT:
The fuel pressure regulator of 1NDTV E/G has a different appearance, but functions the same.
1ND-TV Engine
The fuel pressure regulator receives the signal from engine ECU and adjusts the fuel pressure inside the common-rail.
REFERENCE
Operation of Pressure Discharge Valve/Pressure Regulator
When the fuel pressure of the commonrail becomes higher than the target injection pressure, the pressure discharge valve receives a signal from engine ECU, in order to open the valve and send fuel back to the fuel tank so that the fuel pressure can return to the target injection pressure.
1. At target fuel pressure (common-rail or injection pressure)
2. Over target fuel pressure (commonrail or injection pressure)
HINT:
The fuel pressure regulator of 1NDTV E/G has a different appearance, but functions the same.