In general, it is very important that fuel pressure regulation maintains proper fuel pressure in the fuel system for efficient fuel delivery to the engine. Most engines require between 40 and 60 PSI constant fuel pressure for the best mixture of fuel and air for combustion. This fuel pressure regulator changes the flow to keep it within this range of pressure in any driving condition by regulating how much fuel returns to the fuel tank.
When demand is high-for example, under rapid acceleration-the regulator opens to allow greater volumes of fuel to reach the injectors by reducing return flow to the tank. It allows the increased fuel required for added power output. On the contrary, when idling or under low-speed driving conditions, surplus fuel will be returned to the tank by the regulator to avoid overloading the engine with too much fuel, which will lead to a rich air-fuel mixture and reduced efficiency.
Moreover, fuel-pressure regulators prevent the overload of fuel pumps by maintaining pressure levels to avoid the continuous operation of the pump at maximum capacity. Regulators increase the life of fuel pumps by up to 10-15% as a result of regulating pressure because the pump does not work under high stress constantly.
In a performance vehicle or a racing application, an adjustable fuel regulator would provide a driver with the capability to set the pressure up or down, as specific engine requirements may dictate. An example is that in turbocharged applications, pressures can be considerably higher; sometimes over 80 PSI, because more power requires more fuel. Companies like AEM and Bosch make adjustable regulators for these types of applications and can be adjusted to provide just the right amount of fuel delivery.
Problems with regulators can run the gamut from starvation all the way to excessive fuel consumption. Commonly, in case a regulator cannot hold pressure, an engine will misfire or stall when power is applied. Replacing a faulty regulator usually ranges from $50 to $200 with different models and types of vehicles, but it is a must-have maintenance to keep performance consistent.
The Fuel Pump Regulator is one of the most important aspects of fuel efficiency and health, as well as the performance of the engine, to be able to hold balanced fuel flow governed for the needs of the engine in various driving conditions.