Bad Fuel Pump Symptoms and Replacement Cost

Last Updated on January 16, 2019

The fuel pump is a vital part of any vehicle. It has the responsibility of pumping the fuel from a vehicle’s tank to the engine. Thus, the malfunctioning of the fuel pump can give rise to a disaster on road. A bad fuel pump can cover a certain distance before the vehicle totally ceases to move. The car owners must be aware of the bad fuel pump symptoms so that they can execute preventive steps before an unwanted situation arises.

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What are the symptoms of a malfunctioning fuel pump?

A screeching noise

This is one of the first signs that indicates that there is a problem with the fuel pump. During the normal operation, the fuel pump of a car produces a quiet hum sound. But when it becomes malfunctioned, an excessive loud whining noise is heard and it is definitely the sign that there is an issue.

Engine hard starting

A hard starting is another early sign that is related to the questionable fuel pump. With the constant functioning with the turned on ignition, and the style of operation, the fuel pumps can wear out. When the fuel pump weakens, there is lack of pressure, and it can be challenging to start the vehicle, causing multiple efforts.

Engine performance issues

Decrease in the engine power, acceleration and the fuel efficiency are some of the other factors that clearly indicates that there is an issue with the fuel pump and it must be taken care of. Basically, there will be problems with the entire performance of th engine.

The vehicle will fail to start

When your vehicle fails to start completely, it is a serious issue with the fuel pump. It is a clear indication that the fuel pump of the car has totally been impaired. The engine might crank when the key is turned on, but the car will be in totally no start condition. Instead of doing any self diagnosis, it is essential to seek an expert’s advice.

Read also: Bad spark plug symptoms

The average fuel pump replacement cost

It is very easy to detect a defective fuel pump. Whenever you find that the fuel pump of your vehicle has gone faulty, you must consider it for a replacement, or else you might find yourself stranding on the middle of a road. The average fuel pump replacement cost are between $400 – $600 depends on the model, make and the year of you vehicle. The entire replacement process won’t be more than a few hours. In fact, the labor required for the replacement is also included in the total cost.



    • check when vehicle run, how much is maximum speed
      if fuel pump weak, sometimes a vehicle speed cannot reach even 30km/h then engine stall…

    • Do you park on a hill? Fuel is usually measured from a float attached to the fuel pump assembly. If your vehicle is parked at a steep angle, it may change the position of the float, thus giving an inaccurate reading.

      Additionally, some vehicles do not read the fuel level correctly (or at all) when the vehicle is not running.

  1. Hi. I have a Daewoo lanos 1.6 1998 8 valve. Recently overalled the engine. Driving about a week, the engine fails to start now. There is spark at spark plugs, but no fuel reaching the fuel injectors. Squirting some fuel into the air take the engine starts, as soon as the fuel is finished the engine stalls.
    If I check that there is fuel at the fuel pipe as it comes out of the tank, it is a little when ignition is switched on, but when I switch ignition off and back on there is no fuel. I removed the petrol pump and tested the pump in a bucket of water directly connected to a battery and it had a full and strong pressure stream. I’ve taken off the fuel lines and checked them for blockages but they were clean. As soon as I replaced the pump into the tank, then there is a weak pressure, and not all the time a flow of fuel. It takes several turns before there is a teaspoon full of fuel coming out of the tank. I have replace the fuel pump about 8 months ago. Could you please advise what the cause could be, if possible.
    Kind regards.

    • Test your fuel pump relay and make sure it is fully seated. You may also want to test injectors next. I have heard (but not experienced) that fuel injectors can become clogged if you run a fuel system cleaner through a car with a really dirty tank. Sometimes the cleaner will pick up sediment that clogs the injectors just enough to restrict flow. Good luck on your search. It sounds like you are on the right track.

  2. My fuel mileage display has started to constantly change.. I watched it go from 15.5 down to 11.2 mpg in less than a minute of driving this morning however it ran fine. It finally stayed at 13.6 mpg after a short drive. I have noticed lately it seems to be using more fuel (midgrade). any ideas?

    • Make sure you don’t have any check engine lights. A faulty O2 sensor could cause the car to run rich, which would reduce fuel economy.

      Changing spark plugs is cheap and easy if they haven’t been touched in a while. Sometimes you may see fuel economy decrease when plugs are old and not able to consistently burn the air fuel mixture efficiently.

      Pay attention to any changes in your environment or driving habits. Colder weather reduces fuel economy, as does driving with a lead foot. Stop and go traffic is not friendly on fuel economy either.

      Make sure you’re running whatever octane fuel the manufacturer recommends in your owner’s manual. If 87 octane is recommended, running 89 probably won’t give you better fuel economy.


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