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!

849 responses to “How To Tell If Your Fuel Pump Needs Replacing”

  1. Sam says:

    I have a 2000 GMC Sierra just yesterday it started to sputter when I start it and now today when I tried to drive it I got down the road and it died and now it won’t stay started when I push on the gas. I just changed the fuel filter and its still doing it any ideas what else I can try.

    Thanks Sam

    • ChiltonDIY says:

      Hi Sam.
      Is the vehicle actually running out of fuel or is it an ignition problem? Check the fuel pressure.
      Find the correct fuel pressure specification based on your Sierra’s engine size in your ChiltonDIY subscription by following one of these paths from the navigation outline:
      – Engine Mechanical > Specifications > Gasoline Engine Tune-Up Specifications
      – Diagnostics > Diagnostic Routines > Powertrain > Engine Controls – 4.3L > Fuel System Diagnosis
      – Diagnostics > Diagnostic Routines > Powertrain > Engine Controls – 4.8L, 5.3L, and 6.0L > Fuel System Diagnosis
      General Motors issued a Technical Service Bulletin (TSB #04-08-49-018E) about faulty fuel level senders, did you try adding a few gallons of gas? (The TSBs for your 2000 GMC Sierra are included in your ChiltonDIY subscription.)

  2. Ronnie says:

    Hi everyone my name is Ronnie i have a 04 f150 check engine came on no difference in performance but the code says p0171. What can i check to see what needs to be done

    • ChiltonDIY says:

      Hi Ronnie.
      About the Diagnostic Trouble Code (DTC) P0171: Fuel system too lean Bank 1. Engine started, engine running at cruise speed for 3 to 4 minutes, and the PCM detected the Bank 1 Adaptive Fuel Control System reached its rich correction limit (a lean Air/Fuel condition) —
      Check for vacuum leaks, check the fuel pressure and check for exhaust leaks near where the heated oxygen sensor is mounted. You may have a lazy Bank 1 heated oxygen sensor.
      There is a technical service bulletin that may be related: TSB# 04-17-4 MALFUNCTION INDICATOR LAMP (MIL) ILLUMINATED—SYSTEM LEAN DIAGNOSTIC TROUBLE CODES (DTC’S)—SERVICE TIPS. You can obtain TSBs for your 2000 Ford F150 in your ChiltonDIY subscription.

  3. mchael says:

    i have a 1988 ford bronco II..
    when i turn the key to the on position i dont hear the fuel pump motor kick in but i can hear a click at the gas tank i just got home from an auto parts store and they told me it has 2 fuel pumps one externally and internally.. im not sure which one i need and have NO testing knowledge or equipment.. i noticed you have a 86 bronco II so maybe some help from you can really benefit!

    • ChiltonDIY says:

      Hi Michael.
      Bronco II has two fuel pumps, a low-pressure pump located inside the fuel tank and a high-pressure pump attached to the fuel line about halfway up the body. Troubleshooting the fuel pump requires checking the fuel pressure with a gauge if the pump runs. Have you checked the fuel inertia cut-off switch? The inertia switch is located on the toe-board, to the right of the transmission hump, in the passenger-side foot well. How about the filter, fuses, and pump relay?
      Also there are at least 3 technical service bulletins (TSBs) that may come in handy. Ford released these TSBs when it found that there were recurring issues with certain components. TSBs are one way carmakers provide information to their dealer technicians to help them identify a problem and fix it faster. Ford issued more than 150 TSBs for its 1988 Bronco II. Check your ChiltonDIY subscription for your 1988 Ford Bronco II.

  4. Jeremie says:

    Hi, I have a 93 ranger 4.0. My truck is flooding at idle. When I drive up the road it hesitates almost no power for 1/2 mile then get almost full power for another 1/8 mile then again and again. It has now even gotten to where it won’t take off without having to rev it up. I’ve changed both fuel filters, checked pressure at idle, vacuum lines, exhaust, checked ect,act. It has spark, 3 plugs on right side looks rich and left side looks lean. Don’t know what else to do than checking injectors or valves. code 512,522. Any advice?

    • ChiltonDIY says:

      Hi Jeremie.
      Code 512: The EEC keep alive memory (KAM) test failed. Code 522: The vehicle was not in Park or Neutral during the key on engine off (KOEO) test. These codes may have been set when you ran your test; did you disconnect the battery?
      If the Ranger is running rich on one side check that bank’s heated oxygen sensor. Check for engine vacuum leaks, and are there any history codes? I have seen oxygen sensors that go bad but are not far enough out of the powertrain control module’s range to set the malfunction indicator light.

  5. Ronnie says:

    Thank you will have it checked get back to you soon

  6. Deandre says:

    I have a Suzuki 2005 Forenza and my fuel pump only tests at 40-45 pounds. when is starts, it gives a stutter and it starts at 10-15 pounds. I don’t have the funds to replace it at this time. I have to get back and forth to work. How long do I have, before it quits on me?

    • ChiltonDIY says:

      Hi Deandre. It should be 55-57 psi at idle; your guess is as good as mine. I would plan on checking into your problem ASAP.

  7. marcos says:

    Hello I have a 200 Cadillac devile and at first it was only driving at 13 miles per hour and niw that I’ve been driving it around it’s running good what can be wrong with it I would really appreciate your help thanks

    • ChiltonDIY says:

      Hi Marcos. I would suggest you scan the vehicle to see if you can narrow down your problem. Check all your basics first, plugs, filters and fuel pressure.

  8. Obinna says:

    Hi Clinton,I appreciate the way you solve issues pertaining automobiles.I pray for the continuity.please I have a problem with my Generator(lister).I filled the tank with 10 litres of Gas,while I was using the gen,along the line,the gas was about finishing so I went and switched it off.I later again filled the tank with 20 litres of Gas.Then on switching it on,it refused to start.I tried and tried but it refused.please what do I do

  9. esmeralda says:

    I have a 2002 Mitsubishi lancer it runs fine. But has a little trouble starting and shakes a lot. Once the car heats up to the middle it stops to shake.

    • ChiltonDIY says:

      Hi Esmeralda. Have you serviced the vehicle, checked the plugs and filters? Is the service engine light on? The Lancer could be running too rich or lean at start up. Scan the vehicle to see if any related diagnostic codes are present.

  10. Aaron Moore says:

    I have a 2000 Cadillac deville that stalls periodically now I’ve replaced coil pack spark plugs and all o2 sensors now I’m still having the same stalling and sometimes I hear a clicking noise when I accelerate. When I had it scanned the o2 sensors which have already been changed still shows up as well as gas cap and egr system ..please help

    • ChiltonDIY says:

      Hi Aaron.
      What size engine does your 2000 Cadillac Deville have? What are the actual DTC codes? Usually if you have both front 02 sensors upstream malfunctioning it is due to a rich or lean condition. It could also indicate vacuum leaks or the mass airflow sensor (MAF). You can remove the EGR valve to check to see if the passage is clogged with carbon.

  11. dennis f says:

    I have 97 jeep cheroke I did not drive it for a few months then boy did back and fouth to work for a week or two then it sat around for while boy started it every couple of days one day in I went to use it started and stalled like in ran out gas but there was gas in it then would not start 2 days later it started again and did same thing ran for a few mintes it dos same thing every time have any ideas

    • ChiltonDIY says:

      Hi Dennis.
      Check to make sure you have good fuel pressure and hot spark at the plugs. Scan the vehicle for related diagnostic codes.

  12. Mathew G says:

    I was recently given a 02 Ford Explorer that sat sat with mo gas in it for 2 years. I replaced the battery, start and all fuses that were bad. I put 2 gallons of fresh gas in it, but henever I try to start it up it won’t turn over. All the spark plugs are good and it only starts up with Starting Fluid. Does it matter how much gas I use to get thw fuel pump working or is it just need replacing

    • ChiltonDIY says:

      Hi Mathew.
      Look for the fuel pump cut-off switch or inertia switch. This is a small box with a plastic button on top and an electrical connector at the bottom. This should be located in the luggage compartment. Look on a side panel for a small, round button which you can pry off with a small screwdriver. Through this access hole you will be able to see the reset button on top of the inertia switch. If the vehicle was towed or bounced around it will trip the fuel cut-off switch causing the fuel pump to shut down.

  13. Shawn Morris says:

    I have a 2002 VW Jetta with a 1.8T engine. My issue is, the car will start and idle fine, but as I’m driving down the road it will lose power until I pump the accelerator and it comes back. Also, seems to happen more frequently at a half tank as opposed to full.

  14. missp says:

    Hi, I have a 00 Lincoln ls, today wen I was driving my vehicle it was making this rough. Rumbling noise wen driving. I also can smell a bad gasoline odor outside of my car. Last couple months I replace one of the coil parts I guess. Also my check engine light is on. Can u give me a idea of wat my problem could be.

    • ChiltonDIY says:

      Hi there.
      Scan the vehicle for diagnostic codes to help narrow down the issue with your 2000 Lincoln.
      If you had a misfire condition it could have damaged your catalytic converter.

  15. Patty says:

    HI I have a 2004 GMC Yukon Xl while I am driving down the road my truck loses power, check engine light flashes and when I mash the accelerator nothing happens, it goes dead and I wait like 5 minutes and it starts up again and goes for awhile longer then stops again. I am so lost right now.

    • ChiltonDIY says:

      Hi Patty.
      General Motors issued a Technical Service Bulletin (TSB) describing an issue that can occur with the 2004 Yukon. The Diagnostic Executive is alerting the driver of potentially damaging levels of engine misfire that could damage the catalyst. If this type of condition is detected, the MIL is commanded to flash on/off once per second during the actual misfire condition.
      The TSB is #06-06-04-046: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430…. Check your subscription for your 2004 Yukon for the TSB; it describes the issue and how to resolve it. You can then determine whether it is the problem you are experiencing with your truck.
      Use the “Quick Search” box in the upper right of the page to quickly locate the TSB using the TSB number as there are more than 500 TSBs and Recalls for the 2004 Yukon at this point.
      Scan the vehicle for diagnostic codes.

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