Charcoal Canister Replacement Option (1 Viewer)

[LostAfrican]

Full disclosure. I just got a P0441 code yesterday so I think I just confirmed my zero status and definitely not hero. It was a long time before I got that code so maybe (wishful thinking) it’s a slightly different issue.

Regardless here is how I hooked up the VSV and the vacuum sensor.

The purge port does go to the manifold. The air in/out goes down the hard tube to the frame. The VSV connects the purge and the inlet connector each to the vacuum sensor.

 

[Pyrenees]

Those of you who cut open the canister, mind elaborating a bit? Like is there a seam from its original assembly at the bottom of the unit, where you can crack it open with a chisel/etc? Also, Has anyone found a reliable thing to re-seal it with, that won't degrade? I'd love to give this $40 mod a whirl before throwing $400 at something that is pretty much just for emissions. It looks like some of you had recurring cracking of the sealant. Is the canister under vacuum or under pressure inside? I already put some new hose clamps on the hoses and tested the resistance of both VSVs per the FSM specs. I can't seem to shake my P0441 code. It's the only CEL I get and it recurs every 1-2k miles. I'd just like to nip that in the bud.

 

[Stralen]

It was a little frustrating. I had to redo the bottom end 3 times before I found a way to get it to stay. I feel like it is pressurized.

I opened mine by using a hammer and carpenter knife along the bottom seam and slowly chiseled around until I broke the seam open.

After emptying I cleaned all the valves with carburator cleaner and wd-40.

Part of the problem with resealing is the way it's mounted to the truck..at least the one under the truck.. there is really a lot of stress and vibration on the seam pulling the box back apart. I tried JB weld twice, but each team it cracked in a few months.

Finally, I did a combination of Permatex Black and 2 large strong tight zip ties around the box, over the JB weld that had started to crack again the 2nd time. The zipties provided strength to stay on, and the Permatex seemed to handle the vibration better.

It's been a year now, about, and this last attempt has held.

I noticed that when it was working, in the beginning a lot of old gas came out of the system for a while, where it was sitting stuck in EVAP for so long. When I realized old gas was stuck in some places, I personally also decided to run some StarTron to break down any ethanol build up anywhere. I feel like it helped.

Now, no more engine light, and truck runs good.

 

[Pyrenees]

@Stralen and @LostAfrican perhaps you all can chime in.

My P0441 code keeps coming back frequently enough now that I guess it's time to nip it in the bud.

I previously put some new worm-gear hose clamps on a lot of the vacuum lines, at least until I ran out of new clamps.

I tested both VSVs with an ohmmeter and they both read exactly within the correct resistance range per the FSM specs. Also, Running a techstream test to manually turn the VSVs on/off was successful. So unless there is an intermittent failure that I haven't detected, I don't suspect either the EVAP or Vapor Pressure VSV to be faulty.

Techstream shows the P0441 code specifically to be a CCV test fail: min 589.82 ms, test value 0.0 ms "tank pressure change value at switching over the purge vsv (from closed to open)" - not sure if "tank" means fuel tank or the canister. I suppose fuel tank.

Also, I'm a little confused on the terminology. I assume the Purge VSV is the same as EVAP VSV, as the other one is called the Vapor Pressure Sensor VSV. Can someone confirm this?

Per DI-86 in FSM vol2 for P0441:
- DTC P0441 /446 occur when evap emissions leak in any of this system:
○ VSV for evap
○ canister
○ VSV for vapor pressure sensor
○ vapor pressure sensor
○ lines between them

- Specifically the reasons for setting for P0441 are listed as follows:
○ "Pressure in charcoal canister does not drop during purge control" 2 trip detection logic.
○ OR... "During purge cut-off, pressure in charcoal canister is very low compared with atmospheric pressure" 2 trip detection logic.

Engine runtime was 267 sec in the techstream freeze-frame data. If it were under 200 seconds, "carefully check VSV for evap, charcoal canister and vapor pressure sensor". Doesn't mention Vapor pressure VSV (DI-87). So, probably don't have to care about that.

Next steps are going to to be running test #6 "check purge flow" on DI-89 in the FSM. DI-92 also has a check for charcoal canister test, definitely going to do this. It seems like the charcoal canister might be the culprit here, in which case I will totally give one of the aftermarket canisters a shot. I did notice looking back over the carfax that it didn't pass inspection in NY when it briefly lived there for one year, so perhaps it was this. NC has emissions inspection and this car has never been subjected to it, but mine isn't due for another four months so I'm going to try and get this resolved before then. Just in case.

 

[Qtonic]

Those of you who cut open the canister, mind elaborating a bit? Like is there a seam from its original assembly at the bottom of the unit, where you can crack it open with a chisel/etc?

I'm not too familiar with the internals of the canister. Is there a place on it, maybe somewhere on the bottom, where a hole saw could be used to refill it and then be plugged with a pvc pipe cap?

 

[Pyrenees]

@Qtonic

From what I've seen on this forum, it's not a simple dump and pump. As an aquarium guy, I assumed it might be possible because I deal with carbon all the time.

There are two separated housings inside the canister, a filter and some springs. Based on the findings people have had here, a small vacuum leak inside the canister can cause an issue. The under-spare canister has also been hard to re-seal. I haven't seen that from the ones in the engine bay, so I might refill it if needed. I'm going to follow the factory service manual.

Who knows what solves it.

 

[Pyrenees]

Part of the problem is that there are two types of canister configurations within the LC/LX 100 series. I have a 2001 and all of this is thankfully on the US driver's side under the hood. It couldn't be more accessible. The later ones, I'm guessing here, 2003+, have it under the spare tire. The charcoal box has the same pieces but it's in a different configuration.

 

[Pyrenees]

@LostAfrican I take it that the pressure sensor VSV does indeed need to be hooked up the way yours is, to be code free? If it took you a year to get P0441 again that's ok by me. Mine happens every month.

I did a lot of further testing based on the FSM, to make sure the VSVs were ok/etc.It definitely looks like it's time to replace the charcoal canister.

 

[Pyrenees]

Alright, I took a reciprocating saw to this bad boy. My daughter got really excited peering out through the back door while I hacked this thing open.

P/N is 77740-60390.

It contained 3 lbs, 4.5oz of charcoal. I refilled it with a 45oz can of activated charcoal from petco and that was plenty. I got the pellets, whereas the original carbon was much smaller and more granular.

The original filters in the canister were in excellent condition. There was a mild fuel smell but that's it. I put enough Permatex ultra black on this thing to survive a nuclear holocaust, and zip-tied it with some HVAC ties that I had (needed this because there's a spring inside this thing).

For $45 it was worth a shot, since I cannot find one of these for less than $450.

 

[kruisinkid]

$404 OEM

77740-60390 - Vapor Canister - 1998-2002 Toyota Land Cruiser | Boch Toyota South

1998-2002 Toyota Land Cruiser - Vapor Canister - 7774060390. Genuine Toyota® Parts & Accessories. Manufacturer Warranty. From the Dealership to your Door. Experts standing by.

toyotaparts.bochtoyotasouth.com

personally, i think chopping the bottom off and refilling is a very silly idea. dont mean to harsh your buzz at all. no amount of permatex or RTV is gonna stay glued together. gasoline is going to dissolve the bond sooner rather than later as has already been documented. i wouldnt view it as a long-term/permanent solution. you could try permatex plastic welder but i kinda doubt that would work either. i have a feeling mine is going to croak soon and I will be coughing up the 400 for a new one. but i will keep digging for a 4 port aftermarket can in the mean time.

 

[Stralen]

I think it looks good. It's pretty much how I did mine, and it's held for a good 15-20,000 miles.

 

[Pyrenees]

$404 OEM

77740-60390 - Vapor Canister - 1998-2002 Toyota Land Cruiser | Boch Toyota South

1998-2002 Toyota Land Cruiser - Vapor Canister - 7774060390. Genuine Toyota® Parts & Accessories. Manufacturer Warranty. From the Dealership to your Door. Experts standing by.

toyotaparts.bochtoyotasouth.com

personally, i think chopping the bottom off and refilling is a very silly idea. dont mean to harsh your buzz at all. no amount of permatex or RTV is gonna stay glued together. gasoline is going to dissolve the bond sooner rather than later as has already been documented. i wouldnt view it as a long-term/permanent solution. you could try permatex plastic welder but i kinda doubt that would work either. i have a feeling mine is going to croak soon and I will be coughing up the 400 for a new one. but i will keep digging for a 4 port aftermarket can in the mean time.

No offense taken, I consider this strictly an experiment. If my vehicle had the evap canister underneath the spare tire, I wouldn't have even bothered. The under-hood one was too accessible for me not to try it. If I'm lucky it will last four months until after the emissions inspection

I haven't come across anything aftermarket that looks good, other than the one mentioned in this thread that ditches the filtered air intake. If you find something please post it in here. The 80-series guys have it really lucky with their canisters and us 100-series guys got stuck with this monstrosity. I bet the 200-series ones come with a low-toner-please-throw-me-away chip, haha.

I think it looks good. It's pretty much how I did mine, and it's held for a good 15-20,000 miles.

In my house that would be 2-3 years. I'm going to make a note here... 3/27/19, 174,100 mi. If it fails I'll report back here.

 

[kruisinkid]

I have the vc120 in my 40 and 80 and it does work great. We are pretty lucky in the emissions department. Now this big expensive complicated brick. Oh well. I came across a couple 4,5, and 6 port ones for a corrola and matrix for about 200$. Ebay also has a few “good used” ones for as cheap as $82.

Imstead of chopping off the bottom, could you have drilled a 1-1/2” hole and emptied most of the media out and refilled and found some kind of plug to plug the hole?

And is it really the charcoal that is thowing a code or the moving parts in the top section get gummed up over the years? Or the attached sensors?

 

[Pyrenees]

Here's my really long answer, in case anyone finds it useful in the future. I pretty much tested everything that I could. The factory service manual was absolutely invaluable and I will continue to recommend people just buy one.

Section EC-5 - Inspect charcoal canister. I basically plugged the various ports it suggested, while blowing through other ports. Yeah, I put my mouth on the canister. ANYWAY, that all passed OK.

Techstream shows CCV test fail: min 589.82 ms, test value 0.0 ms "tank pressure change value at switching over the purge vsv (from closed to open)" - not sure if "tank" means fuel tank or the canister.

I tested both VSVs with an ohmmeter and they both read exactly within the correct resistance range per the FSM specs. Also, Running a techstream test to manually turn the VSVs on/off was successful. i.e. triggered the VSV on or off, blew air through one tube and observed it come out of another tube.

Per DI-86 in FSM vol 2 for P0441:
- DTC P0441 /446 occur when evap emissions leak in any of this system:
○ VSV for evap
○ canister
○ VSV for vapor pressure sensor
○ vapor pressure sensor
○ lines between them
- Specifically the reaons for setting for P0441:
○ "Pressure in charcoal canister does not drop during purge control" 2 trip detection logic.
○ OR... "During purge cut-off, pressure in charcoal canister is very low compared with atmospheric pressure" 2 trip detection logic.

Engine run time was 267 sec in freeze-frame data. If it were under 200 seconds, "carefully check VSV for evap, charcoal canister and vapor pressure sensor". Doesn't mention Vapor pressure VSV (DI-87).

Checked harnesses for shorts.

Measured 4.96V between Vc and e2 on ECM, which is within spec (4.5-5.5V).

Measured 3.28V (step 10) between E2 and PTNK on ECM, although I didn't have a vacuum device to pull on the vapor pressure
sensor. Still, within the 2.9-3.7V spec, so that was good.

Measured 1.86V between E2 and PTNK on ECM (normal spec is 2.0V or less) with vapor pressure sensor disconnected and EVAP VSV triggered "on" via Techstream.

Measured 2.06V between E2 and PTNK on ECM (2.5V or less is normal) after removing gas cap, disconnecting vapor pressure VSV connector and triggering EVAP VSV "on" in Techstream.

As for refilling the canister, I suppose it's possible to drill, but you would need to make two holes because there are two separate containers within it (with an air connection at the bottom, thus the springs). The other issue is the springs themselves. They push off the bottom of the container to compress the charcoal up against the top of the unit. If you drilled the unit out and shook the carbon until it came out, the spring and plate assembly would just fly all over the place inside the unit. I debated just taking the spring and plate out, because it would put less stress on the bottom plate seal, but I wasn't sure if that would cause a problem (they engineered it this way for SOME reason after all). That's where the heavy-duty HVAC zip ties came in. They basically take the pressure of the spring. My guess is that if this experiment fails, it's because a zip tie breaks and the spring rips the seal. Maybe I'll add a couple more zipties for redundancy.

I also found this image online, but it's not in my LX 470 FSM. It shows the codes/pressures/etc. Really helpful to understand the operation of this thing. Yeah, I guess I could have just paid $400 and gotten it over with, but I really wanted to know what was wrong. I ruled out everything that I could. I hate throwing parts at a problem without understanding it.

 

[Stralen]

Your comment on the spring pressing on the carbon has reminded me of something- I wish I had rememebered sooner, sorry, as I'm sure others who did this ran into something similar:

I was somewhat fortunate the JB weld failed the first time, because when it took it apart to reseal it, I swear that the carbon had SETTLED and compressed, and the amount I put in there was no longer enough to fill the canister. It was a good 1/5 the volume. As a result, the filters and springs had room to move, and eventually they became lose inside and moved all around inside the canister. On my second rebuild, I made sure to shake and press the carbon in to get it really, really, really full.

 

[Pyrenees]

I filled it up until somewhere between a half inch to an inch away from the edge. I used pellets. Spring had a lot of pressure. I just added two more zip ties.

 

[kruisinkid]

When they say tank they mean fuel tank. Diagram above makes that clear as (vapor) canister is mentioned with it.

In the 80 series, sometimes a new fuel cap (oem of course) would solve the problem.

The diagram above may not relate exactly to our earlier trucks. Our vapor canister p/n is only good to 2002 and that diagram is probably from the 2003 FSM. I wonder if that exists in the 2004 fsm floats around in Pdf form here...

 

[Pyrenees]

Got a new fuel cap from the Toyota parts counter at the start of my P0441 saga. Sadly I thought for a month that it worked

 

[Pyrenees]

@kruisinkid while you're here and since you have 80-series experience, I want to pick your brain on this.

I don't have an 80-series, but I understand that the canisters are the type with the three-connector "fuel tank", "purge valve" and "air" type. The 100-series like mine also has a fresh air intake that comes off the air intake post-filter. Some folks earlier in this thread basically combined the two "air" terminals... i.e. fresh air and disposal into one. I'm not against trying this if my ghetto factory canister mod fails, but I need to know why it won't work. I don't understand why the 100-series has a virtually unregulated connection between what is gasoline vapors and the freaking intake. That seems like a terrible idea, but then again this is "all about emissions" which we are still very much about in NC. It will be really interesting to see if I pass emissions with the ghetto carbon box. I've never had to pass emissions with this car before, but it was on my mind.

 

[kruisinkid]

the vapor that gets sucked into the intake is after the butterfly so its not as crazy as it seems. and its not pure gasoline vapor, its mixed heavily with outside air. i have been trying to wrap my head around the 100 series system for the last day to try and compare the 2 in my head. the 100 is obviously way more complicated than the 80, but the 80 EVAP is tied up with the EGR system a bit. ive never seen a mention about the EGR system is on the 100. thats for another night i guess.

so looking at the 2004 FSM, our (98-02) setup is maybe similar enough, just in a different configuration?
2004 ports are:
-EVAP (tank)
-Purge
-Air inlet
-Air Drain (vent)

as we have kinda figured out, the air inlet is the odd duck. the air drain is what lets the canister breath and used to be just open to atmosphere. it is in the 40 and 80. it was just a large hose that disappeared down into the frame rail. it looks like the air inlet (which is a vacuum line) is used to operate the VSV for the pressure switch. i dont know how else a VSV on the can itself (right?) can operate without a vacuum line. it may get more complicated with valving direction once inside the charc can, but that is my best guess. i havent really stared hard at the 100 EVAP setup yet, though i did just dump all new EVAP hoses in my parts cart to replace. i did see a couple that were cracked in places, certainly what i now believe to be the air inlet line (the one that is in about 3 sections that goes over the top of the intake manifold on the back half of the engine?)

does that help or did i make it worse? it seems like this system is smart enough to know that there is no vacuum on that air inlet line and then throws a code or rather no vacuum to operate the pressure switch, that fails, then throws a code. perhaps you could tee off another vacuum line with the same diameter coming from the air intake before the throttle body?