General beliefs in replacing a fuel pump vary between 100,000 and 150,000 miles but can be very different based on many factors: fuel quality, driving habits, and maintenance practices. As an example, vehicles always running low on fuel tend to stress their fuel pumps out more than others by about 30%, since the fuel is what cools the pump and lubricates the moving parts internally. Driving it low means that the pump has to work harder, which raises the chances of overheating and early failure. That is why most automotive experts suggest maintaining at least a quarter tank level to help extend the life of the pumps and avoid overloading the system.
Other routine maintenance practices, such as regular replacement of the fuel filter, are equally important to extending the life of the fuel pump. To be sure, regular replacement of the fuel filter at 20,000 to 30,000 miles prevents fuel filter blockage and the buildup of sediment that would otherwise damage the pump and cause it to work harder than it needs to in order to maintain the fuel pressure at the appropriate level. Most fuel-injected engines require a pressure somewhere in the range of 30 to 60 psi, with a clogged filter capable of creating pressure losses that make the engine run lean and put additional stress on the pump. Indeed, studies have shown that cars with clean filters tend to have fewer fuel pump problems and longer pump life, gaining up to several extra years of operational life from the fuel pump.
These symptoms include increased cranking at startup, hesitation, loss of power, stalling, and strange noises that may emanate from the area around the fuel tank. Such symptoms are a signal that the pump has started failing in its work of keeping up the required pressure of fuel, hence creating a need to replace it. Ignoring these signs could result in the total failure of the pump, which, aside from the performance, may result in more serious and expensive repairs should the lean mixture of fuel cause damage to piston rings or valves of the engine.
The driving conditions and environment also affect the life of the fuel pump. For vehicles driven under harsh conditions such as dust, debris, or extremely hot/cold temperatures, their fuel pumps would have to be replaced a lot more frequently. Likewise, off-road driving or high-performance applications that require increased demands from the fuel system-sometimes requiring a lot higher flow rates and pressure levels-can definitely accelerate wear and tear on the pump. Replacing the pump closer to 100,000 miles would therefore be recommended under these conditions.
Replacement of the fuel pump should be done with a high-quality pump that will provide long-lasting dependability. OEM or high-performance pumps cost a little more money, generally in the range of $50 to $300, but are more durable and will not require being changed as often. Proper maintenance and quality replacements ensure optimal performance with the fuel pump. For more information and options on how to take care of your fuel pump, see Fuel Pump.