How To Tell If Your Fuel Pump Needs Replacing

Posted on: by
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!

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

  1. Paul says:

    Today my 1996 Chevy S-10 4.3L lost power as if running out of gas. I pulled over (had to, it stopped running). After a few minutes I tried to start. It started right up. After a short ways, (less than 1/2 mile) ….same thing happened. I thought maybe I was running out of gas. I got a gallon of gas, put it in, started up fine, I took off…same thing in less than 1/2 mile. Called AAA, got towed home. A couple of hours later, I started it up. Initially the engine raced to high RPM then settled down and idled fine for several minutes. I shut it down and did not drive it because I didn’t want to get stranded again. Any help would be appreciated. Thanks

    • ChiltonDIY says:

      Hi Paul.
      When the vehicle shut off was it when you slowed down and came to a stop? Did the exhaust smell funny? If so, I would check the EGR (exhaust gas recirculation) valve if this occurred. If the EGR valve sticks open it will cause acceleration problems and stalling due to a vacuum leak! Scan or have the S10 scanned for diagnostic trouble codes (DTCs). You need to find out if it is a fuel problem or ignition malfunction. DTC’s can help you pinpoint the problem. There are some TSBs that may be related.
      Technical service bulletins or TSBs are released by a carmaker to their dealers when there is a common issue occurring. For example a component that has proved to be faulty. If the component is safety related, then a recall is issued. When it is not deemed to be safety related, a TSB is issued.
      The TSBs and recalls for your S10 are in your ChiltonDIY and your technician’s ChiltonPRO subscription. Two address symptoms like what you describe. One outlines special instructions for the linear EGR valve and the other is regarding the fuel pump pulsator.
      Because there are hundreds of TSBs and recalls for the 1996 Chevy S10, sort by “Emissions” to find the Linear EGR valve TSB and by “Air and Fuel Delivery” for the Fuel Pump Pulsator TSB.

  2. Cindy says:

    I have a 2014 Dodge 1500 hemi its been sputtering, stalling , misfiring and wont go above 20 kph but it seems only when my tank is full as it goes down to 3/4 of a tank it starts to run better gets up to 80 kph still a little sputter and farting but still higher speed . thank god so embarrassing doing 5 kph then dieing on a busy street in a brand new truck. Her prettiness isn’t working anymore to make me like her.

    • ChiltonDIY says:

      Hi Cindy.
      Those symptoms probably set a diagnostic trouble code, or DTC. The truck should be scanned to retrieve the DTCs. These codes identify systems which are operating outside of normal parameters and which may be the source of the problem.
      Since your Dodge is a 2014 it could still be under warranty.

  3. Dale Newnam says:

    My astro van was hard to start but would run fine after it did start , checked fuel pressure at start and it was 48 pounds so I changed the pump and now it runs fine but is leaking gas from the vapor canister purge value. Doesn’t leak untill it’s been running for like 10 MIN.

    • ChiltonDIY says:

      Dale, what year is your Astro van?

      • Dale Newnam says:


        • ChiltonDIY says:

          Hi Dale.
          When the fuel pump module was replaced, the fuel return line and the vapor lines weren’t transposed, were they? That will cause what you’re describing.
          Overfilling the fuel tank can also cause it; when the pump shuts off, the tank is full. Continuing to add fuel will cause raw fuel to enter the canister. If that happens, the canister must be replaced, (it is not designed to handle raw fuel).
          I would inspect and flush the evaporative system and scan for diagnostic trouble codes (DTCs).

  4. Dale Newnam says:

    The van only has about 2 gallons of gas .. so you think when I hooked the fuel lines back up I, I hooked them back up wrong? I probably did knowing my luck .. will check on Saturday .. it was a lot of gas running out of the charcoal canister thing so I need to get another one of those correct? Thanks for all the help

  5. Dale Newnam says:

    One line was smaller then the other 2 and one didn’t have the white snap lock on it. Do you know the order in which they go back on?

    • Dale Newnam says:

      I meant to hit reply, sorry. I changed the whole fuel assembly BTW and not just the fuel pump.

      • ChiltonDIY says:

        Hi Dale.
        Make sure no hoses are pinched. I would pull the tank back down to inspect the situation. If the problem was created after the fuel pump assembly was installed I would start there. Make sure the pump assembly is correct.
        Did you change the external fuel filter when you installed the fuel pump assembly? Always change the external and internal filters when installing a new fuel pump.
        Illustration callouts: (1) Evap line and (2) fuel pump assembly

  6. Dave says:

    I have a 99 eclipse gst 5spd and over the last few months I noticed that the engine would lose power (almost like it would die but restart) when I would take a right turn too fast. Then lately it hasn’t been idling very strong and it will just die out. It died on me going in to work so I pulled over and it restarted after a few minutes and didn’t have any problems getting it back home. Could my fuel pump be the issue?

    • ChiltonDIY says:

      Hi Dave,
      Did you check your fuel pressure? (1999 Mitsubishi Eclipse 2.0L Turbo)
      With the vacuum hose disconnected from the regulator, unregulated fuel pressure is 44 psi. The fuel pressure will be about 10 psi less with the engine idling and manifold vacuum at the fuel pressure regulator.
      Try scanning the Eclipse for diagnostic trouble codes (DTCs) to help verify the problem is fuel related.

  7. Candice says:

    I have gmc jimmy 4wd 4.3 i put new spark,plugs fuel filter,crank senser,idle air control,camshaft senser,mass air senser. And also got fuel,pressure tested and its normal. Also got new vaccum hoses. My vehicle is stallin out on me and back firing. It will stay runnin if i pump the gas an if i get enough speed goin down hill bout 40mph it,stay runnin idk what else to do.

  8. Candice says:

    I got it scanned it just shows the parts i already,put on.

  9. Candice says:

    I just need some advice im runnin out of money and i got to make it to college everyday and have no one to help me.

    • ChiltonDIY says:

      Candice, retrace your repairs.
      Check that the firing order is correct and that the spark plug gap and the spark plug wire resistance are within specifications.
      Make sure the ignition wires and distributor cap are okay. Check that your fuel pressure is within specifications.
      Clear any DTCs that are stored in the powertrain control module (PCM), then perform the crankshaft relearn procedure.
      Only a scan tool can command the PCM to perform the crankshaft position system variation learn procedure again.
      There is a technical service bulletin (TSB) that may be related: “Poor Engine Performance-Misfire, Rough Idle, Stalls, ….” Check it out in your ChiltonDIY subscription for the Jimmy.
      The correct firing order is in the Engine Electrical Section of your ChiltonDIY; for spark plug gap and fuel pressure specifications check out the Engine Mechanical section Gasoline Engine Tune-Up Specifications.
      For the relearn procedure follow these: PATH: Diagnostics > Diagnostic Routines > Powertrain > Engine Controls – 4.3L > Crankshaft Position System Variation Learn, and
      PATH: Engine Performance & Emission Controls > Components & Systems > Crankshaft Position Sensor > CKP System Variation Learn Procedure

  10. Nick says:

    Hi all. I have a 2003 Silverado,4300 engine, 203400 miles on it. Driving home from work yesterday I had the engine sputter,just slightly though. Attempting to go to work this morning,making a turn, engine dies completely and will not restart,engine cranks but does not even attempt to start. No maintenance/repair records available. Thanx

    • ChiltonDIY says:

      Nick, make sure you actually have gas in the fuel tank. There is a technical service bulletin (TSB) for the fuel level sensor, check your Chilton subscription for the TSB: “Cranks But No Start, Stall, ….”
      Listen for the pump to energize, Have a helper turn the ignition switch on while you listen back at the fuel tank for the fuel pump to energize, you should hear the pump. If you don’t hear it then take a rubber mallet and tap on the bottom of the fuel tank. Sometimes you can jar a faulty fuel pump to start. Your fuel pressure should read within specifications. Try spraying a little carburetor cleaner into the throttle body, if the engine kicks or tries to start you know it’s a fuel problem.

  11. Candice says:

    I also put a new crankshaft senser my vehicle ran good for a good hr..its back to the samething.. Also I noticed I have a gas leak and it was pourin from gas tank it lookd as it was comin from the top of tank. If it not one problem its another and we checked firing order and the gap. Everything gud with them. Fuel pressure good

    • ChiltonDIY says:

      Hi Candice.
      If fuel is pouring from the top of your fuel tank, that’s bad. Please use extreme caution when working around the fuel system, and I would not drive the vehicle!
      I believe the fuel tank is of a metal construction. I have seen the top of the fuel tank rust out causing a leak. Sounds like you are going to need to lower the fuel tank to inspect the tank and the fuel lines. Check the evaporative system, this can also leak fuel if the system is faulty.

  12. Terraza says:

    Hi, I have buick terraza 2006 and shut off while I am driving. Usually shot off when is warm and I need to wait for half hour and start again. Can that be my fuel pump?

    • ChiltonDIY says:

      Hi there.
      First I would check the battery and its connections. Make sure the battery is 100% charged and that all the connections are clean and tight.
      Then scan the Terraza for diagnostic trouble codes (DTCs). You need to find out if the problem is fuel related.
      If trouble codes are stored in your vehicle’s computer, the codes will help you determine whether it is fuel related.
      General Motors issues technical service bulletins (TSBs) to its dealers regarding common problems. There are some for your vehicle that may apply, related to the type of gasoline used, clogged fuel injectors, as well as other fuel system components. You can read the TSBs in your ChiltonDIY subscription, filter by system, “Air and Fuel Delivery” or by symptom, such as “Engine Extended Cranking or Hard Start Condition.”
      Note: I have seen faulty crankshaft sensors cause similar problems.

  13. Madonna Bristow says:

    I have a 1999 Dodge Stratus 2.4L 4 Cylinder 16 valve Dual Overhead Cam. My car starts and runs fine in my driveway with no problems. When I go to drive it it dies on me. It sometimes will start back up and sometimes it won’t. My car does not have a fuel filter at all. I have been told by a mechanic that it is a weak fuel pump that is basically getting ready to go out. Which has been told to me when it does go complety out the car will not start at all. I was just wondering what you would think?

Leave a Reply