Various internal or external issues with the fuel pump can cause low pressure within the system. Typically, a Fuel Pump is designed to maintain fuel pressure between 30-80 PSI depending on the vehicle make and model. When the Fuel Pump starts failing, it cannot develop enough pressure to push fuel to the engine. This means that throughout the fuel system, pressure becomes low. This will eventually cause the engine to stall, hesitate, or fail to perform well.
For example, a 2020 study by Automotive Experts International highlighted that nearly 40% of fuel delivery failures were caused by a Fuel Pump malfunction, with pressure issues being the most common symptom. These failures are often the result of clogged fuel filters, damaged impellers, or worn-out components within the Fuel Pump that reduce its efficiency. In fact, Fuel Pump efficiency can degrade by as much as 25% over time due to normal wear and tear, which directly impacts the fuel pressure.
The Fuel Pump works by using an electric motor to create the required pressure. When this motor weakens or the internal components get damaged-a fuel pressure regulator or fuel pressure relief valve-the pump fails to maintain the proper levels of pressure. For instance, a clogged fuel filter may increase the load on the Fuel Pump and make it fail prematurely. According to Tim Smith, an automotive technician, “When the Fuel Pump is unable to maintain pressure, the engine doesn’t get enough fuel, which leads to poor performance and inefficiency.
Low fuel pressure due to a faulty Fuel Pump is also one of the leading causes of performance issues in older vehicles. A Fuel Pump that has been in service for over 100,000 miles may start to show signs of fluctuating pressure as internal components wear down. Automotive repair experts recommend checking the Fuel Pump regularly and replacing it if fuel pressure falls below the recommended range.
Usually, a fuel pressure gauge was installed by technicians onto the fuel rail. Whenever the pressure reading decreases within or lower than the recommended range of PSI, that basically acts as an indication the functioning has gone bad with this pump. A constant dip in fuel pressure during its operating regime indicates that the Fuel Pump will fail very soon.
People with symptoms such as slow acceleration or misfires may want to take a closer look at the Fuel Pump and make sure that it is providing the proper pressure of fuel to the engine.