Fuel Pump “gurgling” noise - help please

[progress4m]

Need help with Fuel Pump “gurgling” noise that I start hearing during my last camping\hunting with my family (truck currently has 82K on it)

Noise can be heard next to the rear left tire (engine idling), and definitely coming from the gas thank around fuel pump area. The noise can be described as gurgling, fluid with air bubbles moving through the pipe. I got under the truck and put my ear next to skid plate of gas tank-confirmed noise is coming from the fuel pump (at that point I had about ¾ of gas in the tank)

After coming home, I have pulled the gas tank skid plate, without skid plate the noise is essentially gone and only can be heard if I put my ear directly on the gas tank, and it is louder where the fuel pump is. (At that point I have about ¼ of the gas left). I have also open access panel (under rear left set) to fuel pump and I cannot hear any noise there, pump actually running very quiet there… and there is no noise from the gas tank fill-up neck with gas cap removed.

My question does anyone have any thoughts\idea if the noise I am hearing is normal or fuel pump is falling..? I know I may be asking too much… but can anyone get under the truck and put the ear on the skid plate next to fuel pump area and let me know what you are hearing?

I was planning long family trip real soon and that is why I am concerned.

Sorry for a long post and Thank you in advance!

 

[Nobody Special]

So the skid is amplifying the sound?



(BTW, You can amplify with a Styrofoam cup on your kitchen sink, and some transmissions, especially manuals and various other vibrating objects)

 

[progress4m]

So the skid is amplifying the sound?

That is definitely correct, without skid plate I can only hear it if I put my ear directly against the tank and the loudest part is where fuel pump is...
The sound doesn't sound normal to me, but maybe it was there for a very long time and I can hear it now because I did remove and reinstalled the skid (about month ago) after removing a small dent in it... so maybe the skid now is touching the tank amplifying the sound... and that is why I have asked if anyone can listen to their fuel pump... maybe I am lucky and it is "normal" sound for 4Runner fuel pump...?

 

[CollinJ]

Have you checked to see if your VIN was included in the 5th Gen fuel pump recall from earlier this year? Could be related, or not but figured I would put it out there in case you hadn’t checked or were not aware.

 

[progress4m]

Have you checked to see if your VIN was included in the 5th Gen fuel pump recall from earlier this year? Could be related, or not but figured I would put it out there in case you hadn’t checked or were not aware.

I did check and since my 4Runner is 2013 it is not included... thx.

 

[fkheath]

All modern cars recirculate the gas, that is, more gas is pumped to the engine compartment than is used. Any excess is returned to the gas tank by a return line. They do that to keep from having vapor lock. What you are hearing is probably the return fuel as it comes back to the gas tank. That would be normal.

 

[KSJ088]

Yep probably the EPA evap. I heard mine making a noise in the garage last week when I was going to mailbox. Never heard it before in the 2 years since new.

 

[progress4m]

Yep probably the EPA evap. I heard mine making a noise in the garage last week when I was going to mailbox. Never heard it before in the 2 years since new.

I believe you are referring to EVAP check (pressurizing parts of EVAP system) that 4Runner does occasionally after 5-6 hours being off…
What I am hearing is not that, the noise in my case is there all the time (when engine and fuel pump are running).

 

[progress4m]

All modern cars recirculate the gas, that is, more gas is pumped to the engine compartment than is used. Any excess is returned to the gas tank by a return line. They do that to keep from having vapor lock. What you are hearing is probably the return fuel as it comes back to the gas tank. That would be normal.

Thank you, I understand and was hoping that return fuel could be the culprit and would made that noise, just not sure why it is so loud now, do you hear it on your truck?

 

[progress4m]

I would appreciate if anyone else can reply with their thoughts\experience on the noise I hear from the gas tank.

 

[fkheath]

Thank you, I understand and was hoping that return fuel could be the culprit and would made that noise, just not sure why it is so loud now, do you hear it on your truck?

I have not heard it on my 4Runner, but then I have not been under the gas tank with the engine running. I have heard it on other cars, though.

 

[progress4m]

I have not heard it on my 4Runner, but then I have not been under the gas tank with the engine running. I have heard it on other cars, though.

Thank you for reply!

At this point, I am assuming (and hoping) that what I am hearing is normal… I have re-adjusted skid plate and now noise can only be heard under the truck with the ear next to the tank around the fuel pump area… and no noise next to truck.

Just as another detail on that noise: the “gurgling” starts a second or two after engine is started, so that delay makes the idea that the noise is generated by the fuel return line is even more plausible IMHO.

I will update this thread if anything changes on my end.

 

[Greydog]

I’ve heard this too, 2019 TRDORP, usually on hotter days for some reason. It’s sporatic though, not sure why. Everything else seems fine, doesn’t seem to be the fuel pump either.

 

[progress4m]

I’ve heard this too, 2019 TRDORP, usually on hotter days for some reason. It’s sporatic though, not sure why. Everything else seems fine, doesn’t seem to be the fuel pump either.

Thank you for your input.

IMHO: Based on my case (and my current conclusion\experience) I would say it may be because your 4Runner skid plate is touching the tank on the hot days (since materials are expanded)-thus noise propagate itself sporadically and on hot day(s).

 

[skyfarm1000]

Did you ever figure out if this noise was normal or not?

I just purchased a 2016 4runner a week ago and noticed a rapid bubbling/boiling sound coming from the gas tank.

 

[Whippersnapper02]

Did you ever figure out if this noise was normal or not?

I just purchased a 2016 4runner a week ago and noticed a rapid bubbling/boiling sound coming from the gas tank.

Normal.

 

[fkheath]

Did you ever figure out if this noise was normal or not?

I just purchased a 2016 4runner a week ago and noticed a rapid bubbling/boiling sound coming from the gas tank.

All modern cars recirculate the gas, i.e. pump the gas to the engine compartment, then any extra not needed goes back to the gas tank. Thus the gas returning to the gas tank can make a gurgling, bubbling noise. Completely normal.

(Gas is recirculated to prevent vapor lock).

 

[progress4m]

Did you ever figure out if this noise was normal or not?

I just purchased a 2016 4runner a week ago and noticed a rapid bubbling/boiling sound coming from the gas tank.

In my case, skid plate was amplifying the sound and that is when I start hearing. I have added two small pieces of rubber between skid plate and gas tank so they are not touching directly and I no longer can hear the pump when I am next to the truck. I have also put over 20k miles on the truck since my original post with no issues, so at this point I am 99% sure that sound is normal.

 

[JustLearning714]

[MENTION=6962]progress4m[/MENTION]

For your fuel tank to skid plate spacers, what type of rubber did you use? I think I am having the same problems with that gurgling sound.

 

[progress4m]

[MENTION=6962]progress4m[/MENTION]

For your fuel tank to skid plate spacers, what type of rubber did you use? I think I am having the same problems with that gurgling sound.

It was a soft rubber, about ¼ thickness, anything similar will work as well.
And since it has been couple of years ago: I have no issues with fuel pump and I do not hear any noise either, so I am pretty sure it was related to gas tank skid plate amplifying the normal operation of the fuel pump.