Skip the auto shop - Our mechanics make house calls

Symptoms of a Bad or Failing Fuel Pump

fuel pump

Bad or Failing Fuel Pump Inspection

by a top-rated mechanic at your home or office

Virtually all modern vehicles that use internal combustion engines come equipped with fuel pumps. The fuel pump is the component that is responsible for delivering fuel from the gas tank to the the engine at the appropriate pressure required to meet performance demands. When the key is turned on, the fuel pump is activated and pressurized, which can be heard as a quiet whine or hum in some cars. The fuel pumps equipped on most modern vehicles are electric pumps that are mounted in the fuel tank. However, some vehicles are equipped with inline or mechanical style fuel pumps. Because the fuel pump is the component responsible for supplying the engine with the fuel required for it to run, any issues with it can cause major drivability and performance problems. Usually a bad or failing fuel pump will produce a few symptoms that alert the driver of a potential issue.

HAVE SYMPTOMS OF CAR TROUBLE?
Get an $80 diagnostic
by a top-rated mechanic at your home or office.

Get a quote · Book an Appointment · Our expert mechanics come to you.

1. Whining noise from the fuel tank

One of the first symptoms of a problem with the fuel pump is a loud whining sound. An old or worn fuel pump may produce a noticeably loud whine or howl when it is running. Most fuel pumps will produce a quiet hum during their normal operation, however an excessively loud whine coming from the fuel tank is usually a sign that there is an issue.

2. Difficulty starting

Another symptom that is commonly associated with a problematic fuel pump is difficulty starting. Because of how they operate (constantly running whenever the ignition is turned on) over time fuel pumps can eventually wear out and weaken. A weak fuel pump may still pump fuel, however the vehicle may experience difficulty starting as a result of the lack in pressure. A weakened fuel pump can cause the vehicle to take more cranks to start than normal, and in more serious cases may even cause the vehicle to require multiple turns of the key before it will start.

HAVE SYMPTOMS OF CAR TROUBLE?
Get your car fixed at your home or office.

Get a quote · Book an Appointment · Our expert mechanics come to you.

3. Misfires and a decrease in power, acceleration, and fuel efficiency

Another symptom of a problem with the fuel pump is engine performance issues. As the fuel pump is what supplies the vehicle with the fuel required for combustion to occur, any issues with it can affect the engine’s fuel supply and cause issues. A faulty pump with low pressure will disturb the engine’s air-fuel ratio, which can cause all sorts of performance problems. Aside from hard starting, the vehicle may experience misfires, a loss in power and acceleration, a decrease in fuel efficiency, and even engine stalling.

4. Car is not starting

Another more serious symptom of an issue with the fuel pump is a no start condition. If the fuel pump fails completely, or to the point of not being able to provide enough fuel for the engine to run, the vehicle will experience a no start condition. The engine will still crank when the key is turned, however it will be unable to start due to the lack of fuel. A no start condition can also be caused by a wide variety of other issues, so having the vehicle properly diagnosed is highly recommended.

Fuel pumps are found on virtually all internal combustion engine equipped vehicles in one form or another. Most fuel pumps are built to last, however over time, as the vehicle enters high mileage, it is not uncommon for fuel pumps to require replacement. Another reason fuel pumps fail is if you regularly keep less than 1/4 of a tank of fuel in your car. If your vehicle is displaying any of the symptoms above, or you suspect that your fuel pump may be having an issue, have the vehicle inspected by a professional technician, such as one from YourMechanic, to determine if the pump should be replaced.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Still not sure about your car's issue?
Diagnose your car
What kind of issue are you experiencing?
Brakes are squeaking
Car is not starting
Car is overheating
Car is shaking (vibrating)
Fluids are leaking
Heating and A/C
Smoke or steam is coming out of the car
Warning light is on
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...
Auto Safety Tips
Driving is more than a way to get from point A to point B. Owning and driving a car can also be a highly enjoyable experience. Whether a person is driving...


Related questions

Q: P0300 code random misfire code

Hi. Several components could cause this problem - old, failing plug wires, old plugs with wide gaps, worn or corroded distributor cap or rotor contacts, failing distributor pickup coil issues, or failing ignition coil packs. Diagnosis with proper electrical testing...

Q: Car shuts off soon after startup- 2005 Cadillac XLR

There is a Recall for the fuel pump on your vehicle (#11E009000). Verify that the dealer performed this specific repair. If this repair has been done, pursue this issue with the dealer or Cadillac Customer Service until satisfied.

Q: Gauges in car going on/off, plus hissing sound

The wire harness connections to the modules have issues with the pins and sockets getting small amounts of corrosion or loose contact causing the problems you are having. The wire harness and connections would need to be checked and cleaned...