Strange humming sound from rear of truck when its not running. - Toyota Nation Forum : Toyota Car and Truck Forums

kramer · 12-08-2005, 10:51 PM

We have a 2004 Sequoia and so far, no problems after 20K miles.

Tonight, I noticed that while the truck was parked in the garage, I could hear a humming sound from the rear area of the truck. I put my ear near the rear tire and verified that this is where the sound is coming from. So, I'm assuming its the fuel pump. (Note: this is the 1st time I have heard this sound.)

So, does anybody know if this is most likely the fuel pump? And why would it be running when the truck is not? (For safty reasons, I parked it outside for now).

Thanks to all who answer.

- Kramer

Cyorke · 12-08-2005, 11:21 PM

There is no reason the fuel pump should be running when the key is turned off and out of the ignition. You can look under the hood in the fuse and relay box for the fuel pump relay. Pull it and see if your noise goes away. If it does put it back ans ee if it starts again. If it does I would remove it until you are ready to start it up in teh morning and go to the Dealer and have them fix it. If it is a 04 it should be under warranty still unless you drive the hell out of it.

kramer · 12-08-2005, 11:29 PM

Quote:

Originally Posted by Cyorke

There is no reason the fuel pump should be running when the key is turned off and out of the ignition. You can look under the hood in the fuse and relay box for the fuel pump relay. Pull it and see if your noise goes away. If it does put it back ans ee if it starts again. If it does I would remove it until you are ready to start it up in teh morning and go to the Dealer and have them fix it. If it is a 04 it should be under warranty still unless you drive the hell out of it.

Thanks Cyorke.

I just went out to check it and its not making the noise anymore. I'd start it up and turn it off to try your suggestion but its starting to rain, its cold, and dark so I'll do it tomorrow if I can't get it into the dealer.

Thanks again for your response.

- Kramer

kramer · 12-09-2005, 09:38 PM

Well, to whoever cares, I brought the Sequoia today into a dealer and they said its normal for the fuel pump to run a little after the truck is turned off.

- Mark

Cyorke · 12-09-2005, 10:01 PM

so did they give you a reason for the pump to run after shut off. Is it for cooling since it is cooled by the gasoline in the tank. I guess it will jsut make sure it doesnt overheat after driving. I cant remember ever hearing it on any other TOyota I have my 94 Camry and a 02 Sienna and neither one of them do it.

***Bakemono*** · 12-09-2005, 10:55 PM

It could also be that its programmed to do that to pressurize the lines so that it reduces the cranking time at startup (no air gaps).

davidbsr · 07-13-2007, 10:48 AM

When I park my '02 Sequoia in the garage, it sounds lik a frog for a few minutes. I traced the sound to the gas cap which was (un)venting suction I think. Take it loose and sound stops. Now we just laugh at it. Ribbit!

Brake Weight · 08-22-2007, 10:38 AM

I always thought that it was the rear AC making the noise.

emknowlton · 09-06-2007, 08:45 AM

I just noticed my '02 making the same noise.

lain2602 · 10-02-2007, 04:21 AM

have an o4 had an odd sound too.. found out if i just open the gas cap it will stop.. but since its simple i dont bother to do it anymore........

MDTRD · 10-16-2007, 12:09 AM

That's weird. I've owned Toyotas since 1975 and I have 4 Toyotas(00 Taco V6, 05 Corolla S, 06 Sequoia Lim, 07 Taco V6) and haven't heard any weird sounds when their shut off. This is the 1st I have ever heard of a fuel pump running after an engine's been shut down, on ANY vehicle, to include fuel injected Chevys and Fords. If this is true, can someone provide some documentation from a manufacturer?

kayaknva · 10-16-2007, 06:58 PM

I just got an 07 sequoia a few weeks back and there was a leaflet in all the sales stuff that explained that it was normal. It was a mass produced handout from Toyota. I can dig it out and type what it says if anyone is interested.

kayaknva · 10-16-2007, 07:07 PM

You guys got me wondering so I went and dug it up. Here is what came with mine, hanging off the gearshift when I picked it up.

INFORMATION
Approximately five hours after the engine is turned off, you may hear an electric motor sound coming under the luggage compartment for several minutes. It is not a malfunction. It is the sound of a pump performing a fuel evaporation leakage check. See owner's manual for details.

There ya go..

Nick G · 10-16-2007, 07:42 PM

Great follow up Kayaknva.. I have not heard that sound yet from my 07 Sequoia . good to know..!

lain2602 · 10-19-2007, 04:30 PM

Whew thanks Kay!! i was thinking why do we need documentation from the manfacturer.. and yet THERE it was u have it!!..