It is believed that fuel pressure regulators relieve over-pressures in the fuel supply line extending between the fuel tank and the internal combustion engine. This fuel pressure regulation maintains the fuel pressure supplied to the fuel injectors at or below a prescribed value.
It is believed that over-pressures in the fuel supply line are caused by at least two sources. The first source includes fuel pressure pulses generated by the fuel pump sending pressurized fuel from the fuel tank to the fuel injectors. The second source includes unintended restrictions in the fuel supply line such as crimps or debris blockages.