Fuel Pressure Regulator
WARNING: This page is about a different car, the 2021 Hyundai Kona. However, it is still accessible from the selected car via links, so may be relevant.
GDI ECM operates fuel pressure control valve with the signal from fuel rail pressure sensor to control optimized RPM and rail pressure.
High pressure pump adds high pressure to low pressure fuel from low pressure pump. Controlling fuel pressure is done by fuel pressure regulator from 40 to 200 bar. Under the abnormal condition of high pressure fuel system, ECM controls fuel system as low pressure.