These pumps have some key mechanisms that always keep the fuel pressure and supply it to the engine at a constant rate. Most of the modern fuel pumps work in a pressure range from 30 to 80 psi, depending upon the requirement of any vehicle. In doing so, the fuel pumps depend upon pressure regulators, which regulate the flow of fuel with demand. It is the pressure regulator that keeps the fuel pressure inside the fuel rail constant for the injectors to supply the correct dose of fuel at any moment. By maintaining this pressure, the fuel pump gives an air-fuel mixture that is optimal for good combustion and efficient engine performance.
The bypass valve plays another important part in regulating fuel pressure. This is a valve that relieves excess fuel back into the tank in case the pressure exceeds the set range. This prevents over-pressurization, which might cause damage either to the injectors or any other part of the fuel system. In the high-performance or turbocharged engine, fuel requirement may abruptly shoot up very high, bypass valve playing an important role in rapidly bypassing fuel for keeping the system stable even under high loads. This capacity for regulation and redirection of fuel flow serves not only to protect the fuel system but also maximizes efficiency in that it prevents the wasting of fuel.
Fuel pumps, in returnless fuel systems, control the pressure directly at the pump and do not use a return line. This is similar to modern vehicles; the reason being, this kind of setup simplifies the system and cuts down on heat buildup, increasing the efficiency by a factor of about 10-15%. The operational speeds of the fuel pump design are controlled by the ECU based on other parameters such as throttle position and engine load. By controlling the speed of the pump, the ECU is able to increase or decrease fuel pressure for precise fuel delivery and lower emissions in most returnless systems.
Electronic fuel injection systems extend pressure management further, working with the fuel pump to make instantaneous adjustments in the flow of fuel. This allows the ECU to easily tailor the fuel pressure to very exact requirements of the engine, something which has now become a must for high-performance and economy-minded vehicles alike. This kind of digital control makes sure the fuel pressure remains within safe and efficient parameters, maintaining consistent power without overloading the fuel pump.
As Henry Ford, one of the pioneers of the automotive world, once said: “Efficiency is doing things right; effectiveness is doing the right things.” Both efficiency and effectiveness owe their origin to the proper management of fuel pressure to enable a Fuel Pump to supply consistent and reliable fuel flow. For further detailed information concerning high-quality fuel pumps, refer to Fuel Pump.