Some issues with a fuel pump are fixable, while others cannot be resolved without a replacement, depending on the specific problem and the severity of the problem. In many instances, the culprit is something as minor as a clogged fuel filter or a faulty relay, which can often be repaired for less than a full replacement. The National Institute for Automotive Service Excellence (ASE) reports that roughly a quarter of fuel-pump problems are electrical in nature, such as defective wires or blown fuses, which can usually be replaced far more cheaply than the entire pump. For instance, cleaning a blocked fuel filter or swapping out a broken relay may restore adequate fuel flow without the inconvenience of the entire Fuel Pump needing to be replaced.
If your fuel pump is blocked with dirt or rust, it may be repairable. Fuel pumps are meant to last for long periods, but it can go bad thanks to contaminants in the fuel in the tank; when this happens, the pump may not function properly or completely seize up. One common repair is simply flushing out the system, cleaning the fuel tank and replacing the fuel filter many times to get the fuel flowing back to the engine. According to the Automotive Service Association (ASA), contamination accounts for approximately 18% of fuel pump failures and much of the time, the pump itself can be saved.
But if the mechanical parts of the pump are irreparably damaged (e.g. the impeller or motor) there won’t be any other option but to replace the pump. A U.S. Department of Energy study, for example, has shown that pumps may show wear ranges of as much as 50%, especially in older cars, with repairs not being possible in those cases. This same study revealed that vehicles with more than 100,000 miles on the clock are 35% more likely to suffer from a failed fuel pump, due to worn components that can no longer be repaired.
This reality is reflected in a statement from auto mechanic Randy Harris: “Fuel pumps are tough, but after their internal parts break down or wear out beyond repair, they will need to be replaced. Replacement is needed in these cases in order to regain full function.”
Though small problems can be mended, the life cycle and performance of the Fuel Pump is truly dependent on the type of issue and condition of the pump as a whole. A full replacement is a much bigger job, whereas regular maintenance like changing out fuel filters and keeping an eye for what might be contamination can stave off issues that lead to bigger damage and result in a full blown replacement.