Charcoal Canister issue

[Army97]

Hey everyone,

I have a very distinct, lower pitched rattle coming from my charcoal canister, that I can hear inside the car when I am stopped. I think it rattles when I am driving also but I can't hear it as well with the engine. It doesn't always do it, and I cannot determine any links between engine temperature, outside temperature, gas tank being full or not, or RPM's. Basically when I stop it will start randomly, and usually when I rev the engine it will go away until the RPM's return to idle (but again it might be that I just can't hear it with the engine).

I took a stethoscope to it, and it is definitely the charcoal canister.

Anyone have any thoughts? Should I replace the canister, is this hard to do? Could it be something else like a clogged vacuum line?

Any thoughts are appreciated, thanks!

 

[T4RunnerSteve]

I literally just changed mine two weeks ago. Got an OEM replacement from ToyotaPartsOverstock - part # 77740-35482 - for $346. I was getting codes P0440, P0441 and P0446 regularly -- diagnosed by the dealer (via smoke test) as needing a new canister. The install was pretty easy... just a little tricky reaching all the hoses/clamps but not terrible. The new one works like a charm -- no more codes, all 7 tests ran successfully and passed CT emissions. Saved over $450 in doing it myself -- they wanted ~$790 to do it.

 

[Army97]

were you getting CEL's because of it?

I have only gotten 2 random Check engine lights in the 4 years I have had the truck and they have always disappeared within a day or two.

 

[T4RunnerSteve]

Absolutely. Those 3 codes came up intermittently at first (a year or so ago) and eventually came up regularly (I would clear them... and they would come back). I believe that the VSV on the charcoal canister itself went bad, but at the end of the day you can't replace just that part (to my knowledge) so you I had to get a new canister. There are VSVs that are separate from the canister assembly -- those can be replaced separately.

What year is your truck? On my 2002 the canister is above the rear axle directly next to the lift for the spare tire (and is actually protected by the spare tire). I've heard that on other 3rd gens it's up in the engine bay.

 

[Army97]

I have a 97 3.4L so the canister is right behind the fuse box.

I am wondering if I could have a clogged vacuum line or something that would cause it. I took a stethoscope to the canister and the rattle is definitely coming from in there, quite a a distinct and nasty noise actually.

 

[Army97]

I think I am just going to go to the yard and pull a canister from another 4runner.

Does anyone know if there are any changes or differences in this part that I should be aware of? Will any other Gen 3 runner have the same canister?

 

[T4RunnerSteve]

I think I am just going to go to the yard and pull a canister from another 4runner.

Does anyone know if there are any changes or differences in this part that I should be aware of? Will any other Gen 3 runner have the same canister?

I'd imagine the 3rd gens with the canister under the truck vs in the engine bay have different canisters. Also, the part # on mine was deprecated (replaced) by a new #. Many of the parts sites online show you what years the part supports... that should be very helpful for your search.

 

[Micah_S]

Charcoal Canister Issues

Hey everyone. Sorry to start up a little different question on this forum. I could not find another one that was similar that answered my question.
I have a 96 4Runner, the charcoal canister went bad and I had it replaced. Yesterday I stopped and there was a steady stream of fuel poring out. It was coming from the vapor hose that is on the very front of the canister.
The bottom of the hose was not connected to anything. I had to drive it home on a trailor. When I got home, it started and drove 10 miles with no problem.
If anyone knows what is going on I'd greatly appreciate some information.

 

[aussiebobaustin]

Hey everyone. Sorry to start up a little different question on this forum. I could not find another one that was similar that answered my question.
I have a 96 4Runner, the charcoal canister went bad and I had it replaced. Yesterday I stopped and there was a steady stream of fuel poring out. It was coming from the vapor hose that is on the very front of the canister.
The bottom of the hose was not connected to anything. I had to drive it home on a trailor. When I got home, it started and drove 10 miles with no problem.
If anyone knows what is going on I'd greatly appreciate some information.

Hi Micah and others, I have a 2002 and the EVAP system is bad and I have to fix it to get it registered. I pulled the charcoal canister and couldn't see any cracks ... one of the vacuum controlled valves ( the one to the filling pipe) was not working ... I removed it and flushed it out and it worked some of the time . I cut it open as it is sealed and it appears the diaphragm doesn't have a spring behind it to provide a positive closing pressure . So I removed about 1/32nd of an inch off the cylinder so there was more closing pressure from the diaphragm itself. I then cleaned up the surfaces with sandpaper and glued with 5 minute epoxy. ( see images )

I agree that the vacuum values should be sold as replaceable items but only see the whole charcoal canister for say $350 or $450.

This isn't rocket science and I was taught to only replace items that are broken but in this case the canister is only partially broken.

I plan to go through the canister checks again ..... then

While it is off, I plan to test the integrity of the filling pipe and will check the fuel tank for any leaks

From studying these 4Runner EVAP issues ... it seems the overflow check valve on top of the fuel tank can crack and leak and the tank filling pipe can have leaks due to corrosion.