Is My Fuel Pump Bad? Top 10 Symptoms of a Bad Fuel Pump

Is my fuel pump bad? We’re pretty sure you have asked yourself this question. The fuel pump is what sends gas to the engine and makes your car run.

If it’s not working, you may have some trouble getting your car started or keeping it running.

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But how do you know if a fuel pump is bad? Here are 10 symptoms that could mean something wrong with this crucial part of your vehicle.

SIs My Fuel Pump Bad? Top 10 Symptoms

A fuel pump will wear out over time like any parts and components. That is why it’s important that you know basic car repair and maintenance.

You won’t be able to tell when your fuel pump has given out, but you may notice a change in your car’s performance due to its failure. A bad pump that isn’t delivering adequate pressure can cause an engine to run lean, misfire, and hesitate when accelerating.

This video explains at least four common signs and symptoms of bad fuel.

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There are more than four symptoms! Here are ten (10) symptoms that could mean there is something wrong with a bad fuel pump:

1. Car won’t start

The most obvious sign of a bad fuel pump is when your car won’t start. This can mean there isn’t enough voltage to get the engine going, or the gas it needs isn’t being sent to the engine.

But, a car that won’t start can also have other problems. So if your car won’t start one morning but starts fine the next day, a bad fuel pump may not be to blame.

You need to ensure that you’re getting spark at the plugs and that fuel is reaching your engine. If not, you need to check other potential causes like batteries and starter motor.

2. Gas gauge fluctuates

The next sign is that your gas gauge may start to move erratically. This could result from the engine not getting enough fuel to keep it going. So although you’re using gas, there won’t be any left in the tank to show up on the gauge.

Another symptom of a bad fuel pump is that the gauge may stop working altogether and not move. This could mean your tank is empty or the sender unit is bad.

3. Check Engine Light lights up

In some cases, the Check Engine light will begin to blink or come on. This is generally accompanied by a noticeable drop in gas mileage as well. The check engine light is a generic indicator of a problem with your car.

So if you notice it coming on, get the car to an auto shop as soon as possible. You may also want to learn an OBD2 code reader to identify the cause of Check Engine Light.

4. The engine sputters or stalls

As a result of insufficient fuel, the engine may begin to sputter and stall out. You won’t be able to speed up much either. It can cause your vehicle to idle slower than normal and even have trouble keeping up with other cars on the road.

If your car struggles to maintain speeds of around 55 mph or higher without having periods of “sputtering” and stalling, that may be a symptom of a bad fuel pump. You can also try replacing the fuel filter to see if that helps make a difference.

5. You have trouble shifting gears

A bad fuel pump may also affect your transmission. If you have trouble shifting gears, it could be due to a failing fuel pump. Because of this problem, you may hear grinding noises when you shift into certain gears. Moreover, others won’t work because there simply isn’t enough power to get them to move.

Cars typically rely on outside sensors to control shift points. You will have trouble shifting gears if there are any engine performance issues.f a car’s fuel system is over or under-filled, and the filter or injection system is dirty. This can also impact gears.

6. Engine knocks or pings

Another symptom of a bad fuel pump is that the engine may begin to knock when you accelerate or ping as you let off the gas. Knocking in your engine, also described as pinging, can mean one of several issues in the ignition or fuel system.

This can result from your car not getting enough fuel fast enough. It has too much gas and creates an imbalance in air/fuel ratios in the cylinder head.

7. Engine stalls at low speeds

A failing fuel pump can affect how well your car can accelerate and how it does at low speeds. When stopping or idling, you may notice that it takes you much longer than usual to come to a full stop as the engine keeps stalling out.

This could result in you having some trouble parking. Because the car has difficulty coming to a complete halt.
A malfunctioning fuel pump can result in low fuel pressure. It means that fuel isn’t getting to your engine at the right time. However, this symptom may also mean other problems with your engine and its components, like a bad fuel pressure sensor.

Look around the fuel lines and check for any breaks in them.

8. Loud whining noise

A damaged fuel pump might make a loud, whining sound that you’ll hear from your gas tank. The pump may also make this noise if you’re low on fuel or the fuel in your tank is contaminated.

If you hear whining while on a run, the noise could be coming from your fuel pump. The pump will also make this noise if you have too little or too much fuel in your gas tank.
Your pump’s normal noise is a low buzz for at least two seconds.

You can hear it while the pump puts pressure on your car’s fuel system.

9. Difficulty accelerating

A dying or faulty fuel pump can cause your car to have some trouble accelerating. A problem with your car’s acceleration is harder to notice than other problems. But you may experience some issues going uphill or downhill.

For example, your car may not be able to accelerate quickly when going uphill. Because the fuel pump isn’t keeping up with where it should be as a result of all the pressure the gas needs to be put under.

Moreover, your car’s RPMs may become erratic, and the vehicle could even die on you in mid-drive. In either case, your engine may begin to sputter and stall out. The issue will make it much more difficult for you to control.

10. Excessive fuel consumption

This final sign is the most obvious if you’re paying attention to your gas gauge. If your car is using much more gas than usual or not getting very good fuel mileage, this could indicate a bad fuel pump.

When it’s not working properly, you may need to fill up the tank much more often than before just to keep going. And eventually even put in more cash after putting less in due to the car’s poor fuel economy.


If you’re experiencing any of these symptoms and think there’s something wrong with your fuel pump, have an expert check it out to ensure it doesn’t need replacing.

If you plan on doing it yourself, ensure you’re working with a trusted mechanic or part seller. Then, install a new fuel pump to keep your car running smoothly. The next question would be, how much does it cost to replace a fuel pump?

You may encounter problems after replacing the fuel pump. So make sure to buy a compatible unit and install it correctly.

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