Fuel pump voltage ratings can directly affect the performance and reliability of a vehicle’s fuel delivery system. Most of the time, the electrical system of the vehicle is 12 volts, which runs automotive fuel pumps, the same as other electrical systems inside the vehicle. A fuel pump is designed to operate at a specific voltage; therefore, keeping the voltage at the right level makes sure that the fuel pump operates at an appropriate level and drives the right fuel volume to the engine. Only 1-2 volts of variance can make a noticeable difference in the output with the fuel pump reducing fuel pressure and ultimately causing an engine to run lean, in higher RPMs, or under heavy acceleration or loads.
A few volts lower, like 10 volts, and the pump isn’t working hard enough to pump 100%. During periods of low voltage, you can see as much as a 15-20% decrease in fuel flow according to the pump’s manufacturer. A voltage drop will translate into a lower voltage that reaches the engine, which means less fuel going into the engine which directly affects combustion and ultimately power. For high-performance applications or vehicles that must have a turbocharger, keeping the fuel pressure up at all times is critical to avoid the dreaded lean condition that leads to knocking and potentially catastrophic engine failure.
Racing and performance applications requiring high-voltage pumps are designed to cushion and sustain larger electrical roots. These pumps typically need a heavier duty wiring layout to maintain voltage and avoid voltage sags. Some performance vehicles even employ 14-volt 16-Volt systems to ensure that consistent voltage reaches fuel pumps and other critical applications. The downside to these pump upgrades is that if the wiring in the vehicle is not also upgraded, it can place an electrical strain on the pumps, reducing their life-span and increasing the likelihood of electrical failures.
In motorsport, where fuel needs to be the same no matter how much demand is being put on it, we see a good example of why this matters when it comes to voltage rating. Voltage stability is especially important in racing settings, as power dips from the alternator could lead to fuel starvations, thus affecting lap times and overall performance. As the experts over at Racing Electronics Magazine elaborate on voltage stability in relation to fuel pumps, “Voltage stability is just as important to fuel pumps as it is to the ignition system.
So just how critical of a concept is voltage rating to the average driver? In fact, the life of the fuel pump will be determined by voltage stability even if it is under normal driving conditions. Continuous voltage decreases can cause overheating and shorten the lifespan of the pump, which enhances the cost of replacement. The knowledge of the voltage rating allows drivers and technicians to select the most suitable Fuel Pump depending on the needs of the vehicle thus providing a secure Fuel Supply System and high-performance Engine overall.