A high-pitched noise from the fuel pump generally indicates damage to the pump itself and is usually related to wear and tear, debris building up, or improper fuel pressure. During operation, the fuel pump creates pressure to transfer the fuel from the tank to the engine. A healthy fuel pump makes a low humming noise, while a high pitched noise means that the pump is working harder than what is required. In most cases, this noise emanates from the fuel pump struggling to supply fuel as a result of its internal components failing, a clogged filter, or too little fuel inside the tank. The motor in the pump cannot create enough pressure, so the pitch becomes higher.
For instance, if the fuel in the tank is low, it might start sucking air and cause a higher frequency sound due to its struggle of maintaining pressure. A fuel pump designed for a 2010 Honda Accord typically operates at 30-50 psi, but if the pump is worn, it may struggle to maintain this pressure, leading to a noticeable high-pitched whine. The noise can be created more prominently at an idle or low speeds by a faulty pump, because the engine requires very minimal fuel, but it is still trying to keep the pressure required by the engine.
Industry data suggests that up to 20% of all fuel pump failures in older vehicles are related to increased noise. For instance, according to Bosch, the usual operational life of a fuel pump falls between 100,000 and 150,000 miles, during which wear and tear on this part may begin to affect the proper function of the part. As internal parts within the fuel pump, like its impeller or motor brushes, become worn, friction goes up, producing higher-pitched sounds.
In addition, a fuel filter that is not well taken care of can cause fuel flow restrictions, hence forcing the fuel pump to work harder. For example, if the filter on a 2016 BMW 3 Series became clogged and blocked the free flow of fuel to the engine, it could result in a high-pitched noise from the fuel pump. This extra strain results in a noticeable sound from the fuel pump, as it struggles to overcome the blockage.
A fuel pressure gauge, for instance, is one of the diagnostic tools used to confirm a faulty fuel pump by checking the fuel pressure of the vehicle. If it is way below what is specified in the vehicle, it points to the possibility of a failing pump. If your car starts making a high-pitched noise from the fuel pump, it’s important to get the issue checked out because it may indicate an underlying problem that could affect engine performance.
If you are looking to replace a faulty fuel pump, a high-quality, reliable pump from reputable sources such as Fuel Pump will go a long way in ensuring optimal performance and reducing chances of future issues.