The fuel pump pressure rating depends to a great extent on the type of vehicle and engine specification. It lies between 30 and 80 psi for most modern fuel-injected vehicles while trying to maintain optimal performance. Traditionally, conventional engine-equipped vehicles operate at the lower end of the scale, at about 30 to 40 psi, while high-performance or turbocharged engines that have greater fuel demands may run much higher, into the range of 60 to 80 psi, accordingly.
Pressure should always be maintained within its prescribed range to ensure that the engine has the right amount of air and fuel for combustion. Running below this range may cause the engine to go lean, resulting in poor performance, stalling, or even potential engine damage. Some studies have shown that a 10 psi drop in fuel pressure could lower the efficiency of the engine by as much as 15%, reflecting on both its power and fuel economy. On the other hand, when the pressure is very high, it leads to a rich mixture; this results in an overuse of fuel, hence contributing to very bad emissions.
High-performance vehicles, especially modified ones intended for high-duty use, such as racing, usually require higher-rated Fuel Pumps over 100 psi. Companies like Walbro manufacture high-flow pumps for high-demand applications, particularly in high horsepower applications over 400 horsepower. These pumps are designed to maintain consistent fuel flow when challenged by operational demands and ensure that the engine does not suffer from fuel starvation.
In contrast, diesel engines are normally applied to the vehicle with lower pump pressure needs, usually within the range of 15 to 30 psi, since diesel fire requires high compression rather than an air-fuel mix found in gasoline-type motors.
In fact, in 2018 alone, a set of low-pressure Fuel Pumps made leading car manufacturers like Subaru and Toyota conduct huge recalls comprising over a million vehicles. These Fuel Pumps could not maintain the required pressure; therefore, all these vehicles ran the risk of engine stalling and poor performance-a clear reason that the rating of pressure should be appropriate.
As Henry Ford once said, “Failure is simply the opportunity to begin again, this time more intelligently.” Keeping the right pressure supplied by the Fuel Pump means there will be no big engine problems and one’s vehicle will perform optimally.
For further detail on rating of Fuel Pump pressure or selecting a correct Fuel Pump for your automobile, please refer to Fuel Pump.