In general, cars are incredible feats of mechanical wizardry. There are so many car parts that have to work in sync for your ride to function properly. While it is frustrating when a part of, say, the fuel system fails, it is inevitable.

Assuming that you have a vehicle with an internal combustion engine, a vital part of the system is a fuel pump. The fuel pump is responsible for moving fuel from the tank to the engine with sufficient pressure the idea air to fuel ratio for combustion to make the motor run. The fuel pump turns on when you put your key in the ignition. Usually, if functioning well, it sounds like a soft hum in the background of your car.

If there are any problems with your fuel pump, this becomes evident very quickly. Having a bad fuel pump can leave your car stranded, so it is important to recognize the signs of a bad fuel pump and understand how much it costs to replace it.

Bad Fuel Pump Symptoms

One of the first things you might notice with a bad fuel pump is that your car sounds different when it is on. A well-functioning fuel pump generally gives off a soft humming noise when your vehicle starts up. If instead you hear a sharp whining sound from your fuel tank, then this is very likely a sign you need a new fuel pump. Either this, or the fuel inside of the pump may have been contaminated or there is simply not enough fuel in the car. The first thing you should do if you hear this noise is ensure that you are not running on empty.

A second consequence of a bad fuel pump is that your car might have a difficult time starting. If your car is not starting well but you do not hear the sharp whining noise mentioned above, it is possible that your fuel pump is still functioning, but weakly. This means that the amount of pressure the fuel pump delivers is less than necessary. If the fuel pump is weak, this means that it takes more cranks to start the engine. Of course, there are many reasons why your car may require a few times to start, but a bad fuel pump is not an unusual culprit.

If you manage to get the car started but your fuel pump is not in good condition, you may notice that your engine sputters, particularly if you are driving at very high speeds. Again, a weak fuel pump does not provide the amount of pressure necessary to create good combustion in the engine, which directly affects the performance of said engine. There needs to be an adequate amount of pressure inside of the engine to create robust combustion. If your fuel pump is having a difficult time doing this, then your engine likely has excess “loose” air in it and won’t run smoothly.

Frequent stalling could potentially be the fault of a bad fuel pump. Pay attention to when you stall: if you happen to stall frequently when the engine is at high temperatures, this is very likely due to a failure, usually from the fuel pump motor.

Another thing to check if you suspect that you have a bad fuel pump is the gas mileage that your car is getting. If you have to fill up your car more often, a fuel pump issue may be the culprit. These pumps have valves inside of them, and if these valves are not functioning correctly, it can cause the fuel pump to deliver too much gasoline to the engine. If this is happening, the excess fuel just gets burned away or leaks out of the vehicle. The fuel is not recycled or re-stored, which is why your gas mileage may go down considerably.

Finally, you may not be able to get your car to start at all. There are many reasons why a car may not start, of course, but if the pump has completely failed your car won’t start because the engine doesn’t have enough fuel to produce combustion. If your car is not starting, it is probably a good idea to get it checked out by a professional so that you can figure out the true cause. Again, this could potentially be caused by a bad fuel pump, but it also could be due to any number of other factors. Cars are, again, complicated creations and require many different systems to be functioning in order to work.

Fuel Pump Replacement Cost

The actual cost of replacing a fuel pump depends on several factors. The first is whether you decide to try and replace it yourself or go with a professional. The second is what kind of car you drive. Some cars have more expensive parts than others.

The cost of an actual fuel pump is usually between $75 and $250, depending on the vehicle. If you are replacing the fuel pump yourself, beyond this it is just the cost of your time. Generally speaking, replacing a fuel pump is considered an intermediate-level task. It is more complicated than, say, changing your oil, but not as finicky as electrical work. If you have an afternoon to spare and some patience, you may be able to save quite a bit of money.

If you decide to go with a professional, you may be looking at a cost of between $400 and $500 to replace a bad fuel pump. Expect the actual replacement to take between 1 to 6 hours, depending on the expertise of the mechanic and the tools they happen to have on hand.

The act of replacing parts such as fuel pumps isn’t exactly the height of joy where car ownership is concerned. However, frequent maintenance of the mechanical wizardry that is your automobile is a necessary part of the pleasure of a smooth drive.

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