How To Tell If Your Fuel Pump Needs Replacing

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Fuel Pump Assembly 1986 Bronco II CC Image courtesy of Marion Doss on Flickr

Fuel Pump Assembly 1986 Bronco II CC Image courtesy of Marion Doss on Flickr

Your fuel pump is obviously important for your car, and it would seem as if your vehicle couldn’t move without one. That’s not always true, though. Some vehicles can limp along with a malfunctioning fuel pump for a few blocks or even miles.

But driving with a poorly performing fuel pump is not good for your vehicle, so it’s important to look out for some signs of trouble before you end up stranded or stalled out in traffic.

The fuel pump pumps fuel from your vehicle’s tank to the engine. If the fuel pump malfunctions, your engine will receive less fuel than it needs. There are some common symptoms for such a situation.

The first and most obvious symptom is that your car may not start at all, or it might start poorly. This poor start will take the form of a sputtering, stuttering, stammering sort of start, as if your car’s engine is only getting a trickle of fuel instead of the amount it needs. Your car may also stall during operation because the fuel pump is bad.

Vehicles can sputter and stall for a variety of reasons, so here’s a follow-up test. Pull your vehicle in the garage or other silent environment. When it’s not running, put the key in the ignition and turn it to the “ON” or “accessory” position. (Don’t try to start the engine.) If you have fuel injection and an electric fuel pump, the pump should start up, making a clicking or buzzing sound.

After performing the above test, if you can’t hear the fuel pump turn on, try this test. Using a fuel pressure gauge, test to make sure there’s enough fuel reaching the engine. You can take your vehicle to a technician for this test, or purchase a fuel pressure gauge at an auto parts store and do it yourself. Near the engine there should be a fuel pressure valve where you can attach the gauge. Find the recommended fuel pressure in ChiltonDIY. Compare your measurement of the fuel pressure with what it should be. If there is less pressure than there should be, that’s a sign that your fuel pump may be faltering.

Of course, there could be a few other problems causing incorrect fuel pressure, such as an obstruction in the fuel line or a bad fuel pressure regulator. If your fuel pressure is too high, suspect the fuel pressure regulator. For more information on diagnosing a fuel pump problem, check out Chilton’s online database for detailed instructions, images, and tips from our certified expert technicians to help you determine whether you need to replace your fuel pump or fuel pressure regulator, clean out the fuel lines, or something else.  Learn more about how to keep your car in tip top shape!

797 Responses to “How To Tell If Your Fuel Pump Needs Replacing”

  1. Cheryl Damm says:

    I have a 2006 Mercury Monterey van. I recently noticed when accelerating a clicking in the gas pedal. I remove my foot and press a little easier and it doesn’t happen. Could it be a sign the fuel pump may need to be changed?

  2. ChiltonDIY says:

    Cheryl, it sounds like your the accelerator linkage is sticking, Not the fuel pump.
    Check the throttle cable operation, make sure it is not binding. Then check the throttle body for sticking or binding, inspect, and clean.

  3. emkay says:

    Hello guys, went on a short trip yesterday and I noticed that when trying to accelerate faster while overtaking another vehicle, the car seems to stall a bit then it picks up speed later on. What could possibly be the problem? Thanks for your anticipated help..

    • ChiltonDIY says:

      Hello Emkay.

      It could be quite a few things. I will need the year, make and model of your vehicle to be more helpful. You could have a fuel or ignition problem.

      Have the fuel pressure tested and have the vehicle scanned for diagnostic trouble codes (DTCs), this could help pin down your problem. And last but not least, when was the last time the vehicle was serviced?

  4. hady says:

    im hady from malaysia..recently i take off my cefiro a31 rb20det internal fuelpump coz it pressure very slow.i use 2 pump n install fuel catch tank..the problem is engine wont start at all,fuelrail is full but when it reach adjustable fuel regulator theres no pressure(0 psi) at fuel return line to tank..please help me..

    • ChiltonDIY says:

      Hello Hady.
      Have you checked the fuel pressure regulator and fuel filter?
      Did you check for leaking fuel injectors?
      What does your fuel pressure read when trying to start the engine?
      Have you scanned your car for diagnostic trouble codes (DTCs)?

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