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!

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

  1. kara says:

    I I have a 2004 ford tarus se and I started the car this morning and it seemed to be puttering ansd then when we started driving it was like heistated and it was like it almost didn’t wanna go. And when we stopped at a light it seemed to feel like it was gonna die. Could u please help me figure out what is going on with my car.

    • ChiltonDIY says:

      Hi Kara.
      Scan the Taurus for diagnostic trouble codes (DTCs). Scanning the vehicle’s computer might help point you in the direction of the problem. Check the running fuel pressure and compare it to the specification. Fuel pump pressure specifications are in your ChiltonDIY subscription.
      Inspect the ignition system. Check the idle circuit, the idle air control (IAC) valve adjusts the engine idle speed. A faulty valve can cause hard starting and stalling conditions. A faulty or dirty mass airflow (MAF) sensor can also cause problems.

  2. latese s says:

    No the car has not had a system scan and yes the light flashes on and off but it doesn’t stay on an it is a 2.4 engine.

    (This comment is in response to question first posed on Dec. 11, 2013.)

    • ChiltonDIY says:

      Latese, I would definitely scan the Grand Am, this will give you a direction to go in. You need to find out if it is a fuel problem or ignition. Scanning the vehicle can help you in pinning down the problem.
      Have you rechecked the fuel pressure? When the vehicle won’t start, check the ignition spark with a spark tester, and test the fuel pressure. This engine is a quad 4 and it is difficult to check engine spark, you may need assistance.
      General Motors issued a technical service bulletin (TSB) that might be related for the fuel sender strainer. The TSBs for your Grand Am are in your ChiltonDIY subscription in the section called TSBs and Recalls.

  3. Erik Hensley says:

    If you don’t have a fuel pressure gauge you can simply push down on the fuel pressure shrewder valve after you turn the key on and see if fuel squirts out.

    If you add propane through the air cleaner to a poor running vehicle and the rpm rises it’s running lean (not enough fuel)

    If the rpm drops or there is no difference in rpm the vehicle is not running Lean.

  4. Jeff says:

    I have a 1992 GMC C1500. Will stall when accelerating up a 30 degree incline, but quickly regain power. also notice that engine will hesitate and back fire, again quickly regain power when maintaining speeds of 60mph if i let off the accelerator but then give gas again (passing in the fast lane. Recently (30 days) replaced fuel filter. Fuel pump or strainer. If either, should I just go ahead and change the fuel tank also?

    • ChiltonDIY says:

      Hi Jeff.
      Do you have a fuel pressure test gauge? Have you checked the actual pressure? Is the check engine light on?
      Have you scanned the truck for diagnostic trouble codes?
      Yes, some tanks have slosh baffles inside which can deteriorate over time. I would remove the tank and inspect inside to see if that is your problem. If you have the cash I would replace the fuel pump.
      FYI, water tends to collect on the top of the fuel tank causing rust at the lines and retainer ring. I have seen situations where the tank, sending unit, and lines had to be replaced.

  5. Melissa says:

    I have a 2000 Toyota 4Runner, 2 Wheel Drive. It starts, but If I drive a short distance and shut it off, I run the risk of it not starting again. And this has happened twice, after putting the Gas line anti-freeze in the tank, it started fine… BUT When it doesn’t start, it doesn’t sputter, it cranks, just doesn’t turn over… Would that be the fuel pump?

    • ChiltonDIY says:

      Hi Melissa.
      Have you serviced the fuel filter in the last 25-30,000 miles? Just a thought since you mentioned the dry gas. I would scan the 4Runner and check the fuel pressure. Try to duplicate the problem. When it won’t start you need to check the ignition system for spark. Then check the fuel pressure to see if it is within specification. What size engine do you have in your 4Runner, a 2.7L or 3.4L?

  6. Daryl James says:

    Is there any tools are diagnostics equipment that you can buy to try this test. I had my fuel pump go out in the dead of winter a few years ago & it was impossible for me to pull it in a silent environment as it was during a storm. Thanks for the help.

    • ChiltonDIY says:

      Hi Daryl.
      That is a good question. The best way to check the fuel pump operation is with a fuel pressure gauge. Fuel pressure gauges are not that expensive, just make sure to purchase an adapter if needed. Some vehicles use special adapters to connect to the fuel systems.
      Listening for the pump to energize can be difficult in noisy areas. You can remove a fuel line or if your vehicle is equipped with a testing port, push in on the Schrader valve to check for fuel.
      Last but not least spray throttle body or carburetor cleaner into the intake, by way of a vacuum source for vehicles equipped with a MAF sensor. If the vehicle kicks and tries to start, you are lacking fuel.
      To explain this last test a little more, vehicles with a closed intake system use a mass airflow sensor (MAF). To add an external combustible spray you need to find a vacuum hose connection at the intake manifold. If you remove the intake hose on a MAF fuel system, it will affect the starting and running of the engine, due to the fact that no air will be pulled across the MAF sensor. Some vehicles have throttle body injected fuel systems, in this case you can remove the intake cover and air filter and spray directly into the throttle body.
      This is a General Motors throttle body without a mass airflow sensor (MAF):

  7. Bryan says:

    I have a 1993 GMC K1500 with a 5.7L (350). It starts fine but then the idle starts going up and down and sometimes, but not often stalls. If I don’t let it warm up for 5 minutes before I go it will randomly stall and sometimes hesitate under acceleration. Sometimes I get a Code 44 Lean Exhaust code. Runs much better when warm but very poorly when cold. Fuel pressure is within normal range and I recently replaced the fuel filter, IAC valve MAF sensor, distributor, plugs and wires and many more parts. Could it still be a failing fuel pump? I don’t want to spend the money if I don’t have to and I can’t figure out what’s wrong with this truck.

    • ChiltonDIY says:

      Hey Bryan, I would double check for vacuum leaks (hoses, gaskets, seals). Make sure the exhaust gas recirculation (EGR) valve is not stuck or leaking. Check for exhaust leaks upstream of the oxygen sensor.
      Test the fuel pressure again and check the volume it pumps. What fuel pressure reading did you have? Is the K1500 throttle-body injected?

      • Bryan says:

        I have checked several times for vacuum leaks and could not find any. I have checked the EGR valve and it is fine. There seems to be a couple very small leaks where the exhaust manifold bolts to the block. Yes, the truck is throttle body injected. I got a fuel pressure reading of 9 PSI.

        • ChiltonDIY says:

          Bryan, if you have an exhaust leak it can introduce air into the exhaust, and that would set code 44. But it should still start up with a fast idle. Have you checked out the temperature sensor? Do you know if the vehicle goes into closed-loop operation? (You need a scan tool.)

          • Bryan says:

            The truck starts with a fast idle (around 1100 or 1000 RPM) then soon after starts going down, then back up, then back down etc. Once the engine is warm this problem goes away and it runs smooth and doesn’t stall. The temperature sensor was recently replaced. I did an on road test with a professional scan tool, and yes, it does go into closed loop. I appreciate your time and help very much.

          • ChiltonDIY says:

            Bryan, try setting the base idle by following these steps:

            1) Pull the vacuum off of the bottom of the air cleaner and lay the air cleaner aside. Plug the vacuum lines.
            2) Remove the plug over the idle screw located on the right front of the throttle body.
            3) Start the engine and let it run until it warms up.
            4) Turn off the engine and leave the ignition key in the “OFF” position.
            5) Unfold a paper clip and bend it into a “U” shape. Push the ends of the paper clip into the “A” and “B” terminals of the ALDL (assembly line diagnostic link) connector, also called the “diagnostic connector.” The “A” and “B” terminals are located on the top right of the connector.
            6) Unplug the IAC valve (idle air control valve).
            7) Start the engine.
            8) Insert a T-30 size Torx(R) into the idle adjustment screw. Turn the screw to adjust the idle speed to 650 rpm +/- 50 rpm.
            9) Turn off the engine and disconnect the negative battery cable. Reconnect the IAC valve. Install the air cleaner, and remove the paper clip from the ALDL connector.
            10) Reconnect the battery terminal after about 5 minutes.
            11) Test drive.

  8. Bree says:

    I have a 1998 Kia Sephia, that everyone believes the fuel pump went out. I was driving down a road going about 40-45 mph when it all of a sudden just turned off. I pushed the gas pedal and nothing. Everything inside was still working (lights, radio, etc.) I pulled over and could not start the car. Can you please give ideas to what it might be? And no, it did NOT run out of gas. It was at half a tank from me putting gas in a few days before.

    • ChiltonDIY says:

      Bree, I would check for a broken timing belt. If it is the timing belt the engine will turn over fast due to no compression.
      Check the ignition for spark at the spark plugs and check the fuel pressure.
      If you don’t have a fuel gauge spray a little carburetor/throttle body cleaner into the intake manifold. If it is a fuel problem it should kick the engine to try to start up.

  9. Bryan says:

    I did the procedure, and when I got to step 7, the truck was running at around 1600RPM. I turned the adjustment screw all the way back and couldn’t even get close to 1000, let alone 650. I turned the screw back a few turns and continued the steps, and when I got to the final step, the engine would start, then stall… i adjusted the screw again and the engine is now running at around 800RPM at idle, but anything lower than that just makes the engine stall.

    • ChiltonDIY says:

      Hi Bryan. If it is idling at 800 rpm out of gear, that should work.
      Are you positive there are no vacuum leaks? How is the cold start up now?

      • Bryan says:

        I am 99% sure there are no vacuum leaks. It starts and runs fine but if i don’t idle it for 5 minutes before driving it hesitates when I accelerate. It has no power for a few seconds then it regains power and takes off.

        • ChiltonDIY says:

          Bryan,
          There is a TSB (technical service bulletin) that should be considered after all you have performed all the diagnostics to resolve the problem.
          It is a computer update. A new revised memcal (PROM; programmable read-only memory) should be installed inside the ECM (engine control module). It is TSB# #37-65-11; you will find it in your ChiltonDIY subscription.

  10. carl smith says:

    I have a 2004 chevy venture van it starts bit only runs for a few mins..then shut off

    • ChiltonDIY says:

      Carl, make sure you actually have fuel in the tank. GM issued technical service bulletins on the fuel level sensor, some vehicles may read incorrectly.
      Can you hear the fuel pump energize and run? It should hum back at the fuel tank. If you have a fuel pressure gauge check the fuel pressure. If you don’t have a gauge, check to see if you have pressure at the fuel rail test port. Cycle the key on and off 3 times. With the key off, remove the cap and push in on the schrader valve. Use caution when pressing in on the schrader valve at the test port. The fuel system has over 50 psi. Have shop rags around the test port to catch the fuel.
      Have you scanned the vehicle for diagnostic trouble codes?

  11. Brant Belcher says:

    I have a 1995 Crown Vic that has been showing no signs of problems until now. I drove it to work and back home and the next morning it would not start. I am suspecting that the fuel pump is not working, and I do not hear it when I had somebody turn the ignition on. Before I go replacing the pump, is there anything else I should check. By the way I did replace the fuel pump relay and the fuses are all good. I am wondering if there is a way to check with a multimeter to see if it is indeed a fuel pump malfunction, or could it be a problem in the wiring, relays, etc.

    • Bryan says:

      I would check the ground wire that runs from the pump to the frame. I just replaced the pump in my truck and the reason it wouldn’t turn on was because someone poorly repaired the ground and there wasn’t a good connection through the whole wire.

    • ChiltonDIY says:

      Hi Brant.
      Using a digital volt ohmmeter (DVOM), check for the correct voltage at the fuel pump electrical connector.
      If the pump is getting a good voltage supply, the ground connection is good and the fuel pressure is not within specification, then replace the pump. Follow this path on the navigation tree in your ChiltonDIY for the correct fuel pump specifications and testing procedure: Fuel Systems > Gasoline Fuel Injection System > Fuel Pump > Testing.
      Check that the inertia switch is reset before diagnosing the power supply problem to the fuel pump.
      Have you checked the PCM (powertrain control module) power relay?

  12. Richard says:

    Hi,

    I am having some problems with my 2001 Pontiac Sunfire, this week I was driving and the car turned off twice at two red lights but worked fine on the freeway. Now the car does not start and I have been told its the fuel pump from a friend. I do not think it’s the battery since when the key is turned all the lights and radio work fine. I changed out the fuel filter thinking it could be that, and it started up and ran idle for a bit then died again. I have bought new spark plugs and am going to try that next, is it more than likely the pump? I hear the buzzing when I turn the key, and even when the key is still turned I hear the buzz if I press on the gas. Any help or tips would be greatly appreciated.

    • ChiltonDIY says:

      Hi Richard.
      Have you checked the actual fuel pressure? Is it within specification? (In your ChiltonDIY subscription for the Sunfire follow this path on the navigation outline: Engine Mechanical > Specifications > Gasoline Engine Tune-Up Specifications — for the correct specification.)
      I would scan the vehicle for related DTCs (diagnostic trouble codes).
      Do you have a hot ignition spark to all four cylinders? What size engine do you have?

  13. Dylan says:

    I have a 1994 jeep cherokee.. It will run perfectly for a week or 2 the all of a sudden it will die and not start back up from anywhere between 5 to 10 min…it will do it when im driving and when i stop …and then it will be fine again for a while…i changed the coil and still doing it …please help ..thanks

    • ChiltonDIY says:

      Hi Dylan.
      When the vehicle won’t start, that is the time to check for spark on all the cylinders as well as to check the fuel pressure. Check the Jeep for trouble codes that may help pinpoint your problem. Is it fuel, or a spark problem?
      To check for DTCs (diagnostic trouble codes):
      1. Cycle the key to the “on” position 3 times, leaving it on the 3rd time.
      2. Then count the flashes of the “check engine” light. The 1st digit is flashed…..then second digit. flash-flash-flash………flash flash = code 32.
      Any codes stored in the ECM?

  14. Ben says:

    I have a 2005 dodge durango 5.7,, starts fine, warms for about five minutes, after a mile or so, engine stops, five minutes later starts and runs fine???? outside temperature was -10

  15. chris says:

    I just replaced my fuel pump on my 1976 dodge and it still acts as if its still not getting gas . can it be my sending unit??????

    • ChiltonDIY says:

      Hi Chris.
      What engine and model do you have? Try blowing air into the fuel supply line, remove the gas cap and listen for air. Check the fuel filter. Sometimes the needle valve in the carburetor sticks and won’t allow fuel into the bowl of the carburetor.

  16. styron says:

    I just replaced the fuel pump on 2003 galant it drove perfectly for a week ,then the other day on the freeway I couldn’t gain acceleration. After stopping and shutting the car off, I tried restarting and it was giving the same signs of a bad fuel pump. What could be the problem?

  17. janet says:

    OK now today I goes outside to start my 1998 Tahoe Chevrolet which didn’t turn over, instead it continuously click so I went and bought a new battery and connect it, yet still nothing! so I kept trying. Until it tempts to turn over but slow dragging and hesitation ..And finally it turns over I let it run for like ten mins put in reverse it cut off. While its running I see black ice comes from my exhaust..the car been sitting for about 5 months with no start up..can you please help me pin point this problem???

  18. janet says:

    Oh I didn’t mention my check gauges light on..also when the car running I hear a lot of different sound from the front and back of my vehicle like it’s pooping or a lot of rattling please give me some type of info..

    • ChiltonDIY says:

      Hi Janet.
      If the vehicle sat for months it probably drained or killed the battery. A slow starting condition could have set a check engine light. Check the battery state and the starter circuit; faulty battery cables or a bad starter can cause a slow cranking condition. The exhaust system will produce condensation which when mixed with carbon looks like black ice, that is normal.
      I would let the Tahoe run and warm up. If you can drive the vehicle, check the charging system and starter circuit. Scan the Tahoe for related diagnostic trouble codes (DTCs).

  19. Deb says:

    HI, my husbands F150 started right up this morning in -14 degrees, he let it warm for 5 minutes, droves it about 5 miles to work, shut it off and came back in 2 hours and it won’t start. New battery about a month ago, engine turns over, just won’t fire..what do you think?

  20. Deb says:

    Oh, it is a 2006 F150
    :)

  21. corah says:

    I have or a 93 ford explorer and she wont turn over. I was able to turn her on but when I went to push the gas pump my car turned off. I have replaced the fuel pump, checked the fuses and checked the fuel emergency shut off switch and still haven’t been able to get her to start, she seems to not be getting any power to work the gas pump. What could it be? I am about to blow it up or push her into the nearest lake and say enough.

  22. corah says:

    to push the gas petal not the pump

    • ChiltonDIY says:

      Hi Corah.
      Do you have hot spark at the spark plugs? Have you checked the fuel pressure with a gauge? It should be 35-45 psi. Can you hear the fuel pump run? Is the fuel pressure regulator operating okay? Have you scanned the Explorer for diagnostic trouble codes (DTCs)?

  23. kay says:

    my buick intrigue year 2000 keeps blowing the fuel pump fuse

    • ChiltonDIY says:

      Hi Kay.
      It sounds like an electrical short, check the fuel pump relay and the fuel pump connector for heat damage.
      Disconnect the fuel pump wiring harness connector and check to see if the fuse still blows.
      What size engine do you have in your Olds Intrigue?

  24. Katie says:

    I have a 98 chevy cavalier. I drove it to work fine this morning and drove it home this afternoon. a block away from my house l, while driving, thecarjust stopped running. Car still has full battery and everything electric works. It can’t be the alternator, cuz it still turns over with power on. When I turn it over, it sounds like it wants to start, but wont. How can I tell if its the starter or a fuel pump problem?

    • ChiltonDIY says:

      Hi Katie.
      It sounds like the battery and starter are okay.
      Remove the air filter housing cover and filter, and then spray a small amount of carburetor cleaner or starting fluid in the intake hose. Try starting the vehicle. (Use extreme caution). If the engine tries to start you have a fuel delivery problem.
      What size engine do you have in your Cavalier?

  25. kristine says:

    I have a 97 chevy lumina recently my car is starting to act up and I need to know what it might be now I can be driving down the road and it just shut off on me and when I try to crank it it spits and sputters and me I have to leave it sit to fully cool off before it will start! and then when it starts it runs fine and in a few more hrs it will do it again! what do u think it could be???

    • ChiltonDIY says:

      Hi Kristine.
      Well it could be a number of things. Things to check are: fuel delivery and fuel pressure, and ignition spark at the spark plugs. You will need to determine the source of your problem. First I would scan the Lumina for diagnostic trouble codes. (DTCs). By scanning the vehicle’s computer it may help you to determine the cause of the problem. Things it could be include: ignition components, fuel pump, ignition module, cam or crank sensor, and the powertrain control module (PCM). What size engine do you have?

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