What Are The Signs Of A Bad Fuel Pump?

Here are some bad fuel pump indicators demanding a fuel pump replacement:

1. Weird Sounds

Whining from the fuel tank can indicate a dying pump. Backfires and sputtering engines can also suggest a broken fuel pump.

In general, any weird sound from your car is never good, so always pay attention.

Note: Any of these sound issues may trigger the check engine light on the dashboard.

2. Diminished Engine Performance

There could be a loss of power if your car’s fuel pump can’t provide the engine with sufficient fuel. Also, if the fuel delivery issue is erratic, you might experience surging or sputtering. A less noticeable fuel pump issue can be a decrease in gas mileage. 

In any of these cases, you may need a new fuel tank pump.

3. Difficulty Starting

If the fuel pump can no longer supply the required fuel to the engine, your car will experience starting difficulties. Start-up may take a few seconds longer than usual, or you’ll need a few attempts to get the engine cranked. 

Ignore the issue, and eventually, your car simply won’t start. So don’t ignore a fuel pump replacement!

4. Misfiring 

Many things can cause misfiring, including a malfunctioning fuel pump. 

If the engine isn’t getting adequate fuel, it won’t have the proper air-fuel ratio in the combustion chamber — leading to inefficient combustion. This results in a misfire.

5. Unable To Maintain Speed

If the engine is choking or struggling to maintain speed, you may think you’re out of gas. Check the fuel gauge. 

If the gauge shows fuel in the tank and yet the car’s choking, you have a failing fuel pump.

6. Overheating

A faulty fuel pump can overheat. Due to its inefficiency, it can, in turn, overheat the engine. 

If you have an overheating fuel pump issue, the vehicle might run for about 15-30 minutes before halting. After letting your engine cool, it’ll run again only to come to a halt as the issue repeats.

7. Engine Surges

A failing fuel pump can send too much fuel to your engine. This’ll result in the engine surging, which means the vehicle picks up and then drops speed — making driving dangerous.

8. Low Fuel Pressure

Test your fuel pressure to spot the cause of a faulty fuel pump. 

Is the pressure low? The fuel pump is probably becoming slower or damaged inside — making it incapable of pushing enough fuel to the engine.

You can either buy a fuel pressure gauge to measure the pressure or let a mechanic help you.

Note: Find the recommended fuel pressure in your owner’s manual.

How Much Does It Cost To Replace A Fuel Pump?

A fuel pump replacement cost can be anywhere between $220-$1,062, depending on your vehicle and its age. 

The entire car repair will include a labor cost ($124-$260) and the cost of auto parts ($95-$854).

How Urgent Is A Fuel Pump Replacement?

Driving a car with a fuel pump problem can result in all of the symptoms listed above, including your car running intermittently or not starting at all. That’s why you should get a fuel pump replacement and car maintenance scheduled ASAP.

4 FAQs About The Fuel Pump

Here are the answers to some fuel pump-related questions:

1. What Is A Fuel Pump? 

A fuel pump is a critical part of your engine fuel line system. It moves fuel from your vehicle’s fuel tank to the carburetor or fuel injector in the engine. 

The fuel then combusts, helping you start the car and keep it running.

2. What Are The Different Types Of Fuel Pumps?

There are two kinds of fuel pumps depending on how they operate:

A. Mechanical Fuel Pump

Older vehicles with a carburetor will have a mechanical fuel pump with plunger-type or diaphragm pumps. You’ll typically find this kind of pump mounted on the engine block with the engine’s camshaft working the pump.

A mechanical fuel pump uses a pulling force to move gasoline through the different car components. The fuel is controlled with an inlet valve. It closes when fuel in the carburetor’s float bowl is filled and opens when more fuel is required. 

A mechanical fuel pump may be more convenient, less costly, and easier to access than other pumps.

B. Electric Fuel Pump

You’ll find an electric pump in most modern vehicles with a fuel injection system. This fuel pump doesn’t have a diaphragm or plunger to pull gasoline. Instead, it uses an electric motor to push gasoline through the different components and a pressure regulator to regulate fuel.

An electric pump can be mounted inside the fuel tank on a bracket. You can access the pump from an access port on top of the tank. An electric pump is designed to let it stay submerged in gasoline. 

An external electric fuel pump also exists. It sits outside the fuel tank.

3. ​​Can I Replace The Fuel Pump Myself? 

If your fuel pump isn’t pumping adequate fuel to keep up with the engine, it may need replacing. 

You can do this auto repair yourself. However, we don’t recommend it because dealing with gasoline (highly flammable) must be done by experts.

WARNING: Remember you’re handling gasoline, so:

• Don’t smoke when working on the fuel system. 
• Keep all sources of flame or sparks away from the vehicle and fuel tank.
• Ensure you have a fire extinguisher.
• Use LED lights instead of halogen lights if you’re working at night. Halogen lights get very hot, which can be dangerous around gasoline.

With all the warnings in mind, let’s check out the fuel pump replacement guide:

1. Park your car on a level surface and set the parking brake.
2. Locate the fuel pump in the fuel tank and have a friend turn the key to the ON position — while you listen at the filler opening. Your fuel pump should hum for 2-3 seconds. If it doesn’t, replacing the pump is essential.
3. Now find and verify the fuel pump fuse and relay. If the fuse is damaged, replace it with a new fuse (same amperage). 
4. Once done, check the fuel pump’s operation. If the pump works, you’ve done it! If it doesn’t and the fuse and fuel pump relay function perfectly, check for power and ground at the fuel pump. If there’s power and ground, your pump is flawed.
5. Relieve the fuel system pressure. Disconnect the negative battery cable.
6. Drain as much fuel you can from the fuel tank. Disconnect the filler fuel hose and the electrical connection to the fuel pump.
7. Support the fuel tank using a jack stand and a block of wood. Remove any retaining straps or bolts attaching the fuel tank to the frame. Then lower the tank.
8. Disconnect every fuel line and extract the fuel pump from the gas tank. 
9. Compare the new fuel pump to the old fuel pump to verify if you have the correct part. Once verified, install the new fuel pump by connecting every fuel line to the pump. Reinstall the straps and bolts. Reconnect the filler fuel hose and the electrical connector. Finally, reconnect the negative battery cable.
10. Now fill the gas tank with gasoline and conduct a road test to verify new pump replacement success.

Note: Don’t forget to replace an old, clogged fuel filter during the fuel pump repair, so your new pump can operate smoothly.

4. How To Make The Fuel Pump Last Longer?

Here’s how to avoid fuel pump failure and make your pump last longer:

• Avoid regularly driving with low gas in your gas tank to reduce fuel pump stress. 
• Ensure your gasoline is free of impurities.
• Avoid accumulating dirt and debris in your gas tank opening or around the fuel pump assembly. This’ll reduce fuel filter blockage.

Note: A fuel pump accumulates contamination and experiences wear and tear over time. It’ll start showing signs of damage after 7-8 years or 100,000 miles.