Whistle from charcoal filter with engine off?
 

Hey all;

My '96 Limited has always had a "whistling" or "soft moaning" sound which comes from what's labeled as the "charcoal filter" in my Chilton's. This is the black box mounted on the driver's side wheel well, with the two "moon base" looking humps on it.

I only really notice it after the engine is shutdown, but I'm fairly sure that it happens all the time. It'll continue for _hours_. When I first asked the dealer about it (YEARS ago at the first checkup) they said that they all do it and it's normal.

I finally figured I'd ask you guys for a real answer, and to find out just what the box is. :)


Thanks all!

Mark

There is a fix for that, and I believe perhaps even a TSB from Toyota on it.

Gadget may have some info on his website, but I am having trouble getting onto his site right now.

Look here and see if you can find the TSB for it.

Wahoo! "Emissions - EVAP Charcoal Canister Buzzing Noise EG00297 02/28/97".

AllData didn't list it, but you made me remember that AutoZone.com (click on "My Zone" and fill out a profile) has a huge database of TSB's. I found it up there. Thanks Corey!

Okay, so... is this information that I walk into a dealer with and say "please make this happen", or can I get whatever parts from them and do it myself?

Actually, lemme turn that into a generic question - I don't think that I've had _any_ TSB based work done on the truck - ever. Let's pretend that I wanted to drop it off at a dealer and say "here, have fun". Is that something that's plausible to do, and are they just gonna take my Visa card hostage?

And if I do this, then do I pull the mods out? Eeek!

Mark, I work for a Toyota dealer in Seattle I can check on that Tuesday for you. I'll PM you my phone #. Daryl

Dood! Right on!

You've got Pmail btw... Wahoo!

Thank you!

TSB
 

My 96 taco 2.7L does the same thing I have always thought that it was normal.
So it is not normal?


Red

Normal???
 

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.

No, it _IS_ normal in the sense that a LOT (MOST!) of the trucks do it. It's not harmful, it's just back pressure bleeding through the EVAP system.

But, there's a "fix" for it that you can do which requires replacing the charcoal filter. That'll cost ya' a certain amount of cash - not a lot though.


If it drives you nuts and you really want it to stop, then loosen the gas cap to relieve the pressure in the tank. It'll stop until the pressure builds again (like if you leave the truck in the sun).

(thanks for DarylD for pointing out the gas cap trick to me)

TSB
 

This is a curable and easy thing to fix. There is no removing or replacing anything. There was an additional "canister" created solely for the purpose for stopping this annoying buzz. Because it’s not a standard part the tard at the parts counter will probably look at you strange. I cant find my receipt to give you the precise part # but what I'd suggest is asking the service dept. for the part# for TSB EG002-97 & go from there. It's about $15.00. All your doing is running a existing tube to the new canister that adheres to the side of the EVAP then to the EVAP intake. Takes 2 minutes. Check the install I posted above.