pilsen

Can anone identify a part in the engine for me?

I have a 97 4runner 4WD V6

http://www.hboss.net/4runner/brake-fluid.jpg

NOT the part pointed to by the yellow arrow (brake fluid), but between it and the fuse box- THE BLACK BOX W/THE 2 HUMPS.

Every time I finish driving some distance, the box makes an intermittent buzzing sound for several minutes. Would anyone know what and why this is? Thanks.

Hyperlite

Did yo look behind that box towards the firewall, there is a small red cap with a hole in it connected to a wire. I thought that it is a speaker (buzzer) of some sort. When I fixed my motor after hydrolocking my alarm began to beep when setting it from that location, but it quit soon after the motor was running and has not beep again.......that's not much help is it

4runner4ever

That's a vacuum solenoid. No idea what's its for but I know that it isn't supposed to make any noise. Perhaps a vacuum leak causes the sound?

rimpainter.com

You are talking about the infamous charcoal canister buzzing. Its part of your emission control system I believe. Its a $20 replacement to go to the non-buzzing type. Give TOR (Todd) a ring if you want a new one. He could hook you up.

My truck does it too, but I like it. I think of it as my truck snoring.

AznSky

it sounds like my truck has asthma and is dying haha. My poor baby....

pilsen

Your posts were funny, yet informative. Thanks for the info.

goretro77

I just wonder if eventually this thing can drain the battery? I mean, people say it just keeps buzzing and buzzing. Eventually doesn't that take a toll on the battery?
I just drove in from work, and shut the engine off, a minute later, the buzzing started for mine.

Mystickal

I don't think the sound is electrical in nature - I believe it is pneumatic.

In other words, it doesn't drain the battery. It's just passing gas (air - not gasoline)

I say this because the TSB that fixes the problem directs the installation of an expansion plenum, presumably, this would be for gas expansion.

~Bill

Jonathan

The buzz is coming from the charcoal canister (like Christian said). It's not electrical and will not drain the battery. It won't hurt your Runner at all it's just an annoying sound. You can get a newer canister to stop the sound if it annoys you that bad. I just let make all the noise she wants

j-dub

Pilsen, I have been wondering about this since I got my 4Runner in late summer. I could pinpoint it to the same box, but did not understand it's pourpose.

Now I feel so enlightened, thanks everyone for the replies.

CLin9383

this may not be true, but one of the techs i talked to in 96 when i got my 4runner said it was to "suck back in the unused gas" or something to that extent..but he said it was normal and showed me that it did it on other 4runners...so ever since then, i just let it be..

rimpainter.com

Have you guys received the notice from Toyota in the mail pertaining to anything “broken” that is related to the fuel and emission control system? It applies to 1996 – 2000 vehicles. If you have not received it yet, stand by, you will probably get it. I am hoping that my fuel sending unit problem and canister buzz will be covered under this new campaign.

Very interesting stuff. Its too bad that the notice I got applied to my old Tacoma. I am still waiting on one for my 4Runner.

Mystickal

More information on that here:

http://www.epa.gov/compliance/resour...aa/toyota.html

The settlement was reached in March of this year, so if you haven't been notified yet, call Toyota.

The best part of this is that the warranty on the evap emissions control system was extended to 14 years/150,000 miles!

You can see if your vehicle is covered here:

http://www.epa.gov/compliance/resour...ta_aff_veh.pdf

~Bill

phosho

$15-$20 part & heres the directions.

X-AWDriver

Ok,now there's three threads about the same thing and phosho has posted the fix in all of them. Whatta guy.

phosho

Well when I first reseached this issue on YT there didn't seem to be a definitive answer and there were a lot of inquirys. There was also a bit of misinformation in the threads so when I got the "fix"I tried to put some resolution to the related threads by posting it. FYI

I'm snowed in if you coudn't tell

CLin9383

mystical, do you know if it's free to get done?

MTL_4runner

Glad to know what that was.

Mystickal

Well, the settlement extends the warranty of the evap emissions system out to 12 years/150,000 miles, so as long as you're still in the warranty period and this is considered part of the evap emissions system, it certainly should be.

Of course, your mileage may very. If you run into difficulties at the dealership, go over their head. And let us know how it works out.

~Bill

phosho

The problem of who gets the bill may be that the system must be considered "broken" or not fuctioning properly. I was told that it is not a malfunction but a noise that is created from the canister working and passing air as it should. It was something that had to be addressed by Toyota because there was such a response to what seems to be a abnormally loud noise thus a part was created to quite this fuction of the EVAP and that is the sole purpose for this part. I was also informed by a tech that this did not work for all 4runners, but a large majority were cured (including mine). Why some and not others is a mystery.