The P0441 Thread

[paulunm]

Are you all seeing these codes hearing a gurgling at shut off when hot? I haven't had the P0441 code for a year or so, but have gurgling/bubbling sounds when I initially turn off the truck when it's really hot (Las Vegas). About 50% of the time I do get some fuel smell in the garage.

Never replaced any parts, tempted to throw a gas cap at it. But I assume my canister is full of fuel?

 

[CharlieS]

I don't experience that, but you are in a much hotter environment than I am, so I don't think that is helpful.

Side note, we drove through the desert going past las vegas on a road trip a few years ago and the outside temp showed 116 degrees. We were wondering out loud who could survive in that climate.

 

[linuxgod]

New VCV's didn't help either, though I'm not entirely surprised, but I figured it was worth the $100 to swap them before going down the canister route.

Then I thought to myself "I wonder if there's any warranty?" So I called the dealer since they did the canister last October (when I was pressed for time) and they said it has a 12 month, unlimited mileage warranty. Dropped off the truck today and they just called to say when they removed the hoses water came out of the canister. We did hit a few muddy and wet crossings in Moab but they weren't *that* deep or for *that* long so it's odd to me that I'd have issues but nobody else would after those.

If the dealer refuses to swap it under warranty I'll likely order one from Serra on the next sale. However it leaves me pondering how to prevent the filter inlet from sucking in water in the future. Anyone have ideas how/where to relocate just the filter mechanism? @grinchy how has your canister been after relocating it to the engine bay... (that doesn't seem like it would be any higher or better protected necessary though)

 

[LvCruiserNewb]

Anybody know how many miles/cycles it takes to clear a permanent P0441 code? I had 2 instances of the CEL with only a P0441 code last weekend in Utah. Cleared both times and have driven over 600 miles and many starts since last clearing it and the permanent P0441 still resides. I scan every time I drive and haven't had any further current codes and dont think any pending either so I have no idea why the permanent one remains. I suppose I'll get the techstream laptop out and try to run the active tests, but the evap monitors I brought up on my OBD fusion seem to indicate the VSV is cycling properly. I have no idea what the expected flow is at any condition but when the VSV goes from off to on you see the actual purge flow go from 0 to some positive number. I will say I have boiled gas at least a couple times since last canister replacement so maybe its shot again.

 

[GrouchyTech]

Anybody know how many miles/cycles it takes to clear a permanent P0441 code? I had 2 instances of the CEL with only a P0441 code last weekend in Utah. Cleared both times and have driven over 600 miles and many starts since last clearing it and the permanent P0441 still resides. I scan every time I drive and haven't had any further current codes and dont think any pending either so I have no idea why the permanent one remains. I suppose I'll get the techstream laptop out and try to run the active tests, but the evap monitors I brought up on my OBD fusion seem to indicate the VSV is cycling properly. I have no idea what the expected flow is at any condition but when the VSV goes from off to on you see the actual purge flow go from 0 to some positive number. I will say I have boiled gas at least a couple times since last canister replacement so maybe its shot again.

P0441 generally takes a long time. The EVAP monitor has to run and complete, and that can take quite a while because very specific conditions have to be met.

Use Techstream, go to Engine ECM, utility, enable all readiness. Type in P0441 (select the “P” from dropdown menu) and check the judgement result.

If it’s not ready, you can run the EVAP utility. Takes 20-ish minutes and, if the system is operating correctly, will run the monitor and take care of removing the permanent status.

 

[LvCruiserNewb]

P0441 generally takes a long time. The EVAP monitor has to run and complete, and that can take quite a while because very specific conditions have to be met.

Use Techstream, go to Engine ECM, utility, enable all readiness. Type in P0441 (select the “P” from dropdown menu) and check the judgement result.

If it’s not ready, you can run the EVAP utility. Takes 20-ish minutes and, if the system is operating correctly, will run the monitor and take care of removing the permanent status.

Very cool. Thanks for the info. I presume the truck is supposed to be idling during the test? I think techstream would tell you the entry conditions on a pop-up window when you select the test like it does before running the AC servo reset but I suppose I'll fire it up and find out.

 

[LvCruiserNewb]

Very cool. Thanks for the info. I presume the truck is supposed to be idling during the test? I think techstream would tell you the entry conditions on a pop-up window when you select the test like it does before running the AC servo reset but I suppose I'll fire it up and find out.

Techstream status says the evap monitor hasn't been run. Went to run it and said fuel temp needs to be below 95F. I live in Las Vegas and my truck is parked outside in full sun all day. I'll check back around late September to see if the evap monitor ran on its own by then haha.

 

[GrouchyTech]

Techstream status says the evap monitor hasn't been run. Went to run it and said fuel temp needs to be below 95F. I live in Las Vegas and my truck is parked outside in full sun all day. I'll check back around late September to see if the evap monitor ran on its own by then haha.

Next time you fill up do it from empty. That fresh tank will be fairly cold for a little while, so you could run the test then. Maybe just pull off to the side at the gas station.

 

[linuxgod]

New VCV's didn't help either, though I'm not entirely surprised, but I figured it was worth the $100 to swap them before going down the canister route.

Then I thought to myself "I wonder if there's any warranty?" So I called the dealer since they did the canister last October (when I was pressed for time) and they said it has a 12 month, unlimited mileage warranty. Dropped off the truck today and they just called to say when they removed the hoses water came out of the canister. We did hit a few muddy and wet crossings in Moab but they weren't *that* deep or for *that* long so it's odd to me that I'd have issues but nobody else would after those.

If the dealer refuses to swap it under warranty I'll likely order one from Serra on the next sale. However it leaves me pondering how to prevent the filter inlet from sucking in water in the future. Anyone have ideas how/where to relocate just the filter mechanism? @grinchy how has your canister been after relocating it to the engine bay... (that doesn't seem like it would be any higher or better protected necessary though)

I ended up buying a used canister off ebay from a 2008 LX with supposedly 75k miles that had been wrecked in the front. Swapped it yesterday morning and after two ~45 min drives with several hours parked in between this morning all the permanent codes are gone.

Out of curiosity I'm going to dismantle the old canister and see if I can better understand what precisely is failing and why. Mine was <1 year old but supposedly had water in it. But it's a sealed system and the dealer smoke tested so if there's water getting in I want to understand how.

 

[gasman4u]

I ended up buying a used canister off ebay from a 2008 LX with supposedly 75k miles that had been wrecked in the front. Swapped it yesterday morning and after two ~45 min drives with several hours parked in between this morning all the permanent codes are gone.

Out of curiosity I'm going to dismantle the old canister and see if I can better understand what precisely is failing and why. Mine was <1 year old but supposedly had water in it. But it's a sealed system and the dealer smoke tested so if there's water getting in I want to understand how.

You should use a torch to get in there. Really tempt fate.

Seriously, if you can post pics as I’m interested in the workings of this thing.

 

[linuxgod]

Started to pull the charcoal canister apart. My canister and the replacement felt about the same weight. No water or mud or any evidence of infiltration with just the hoses off. Air flows normally through it as the FSM says to test so it's not clogged. I haven't cut my canister open yet though I did pull the pump off and take it apart to test. The pump comes off pretty easily (just 3 bolts) and it has a Toyota and Denso part # on it.

Canister with the pump removed. The tiny bit of dirt on the white filter in the canister was from my finger.

There's a metal retaining ring around the pump housing that I pried apart as I didn't really see a way to separate it otherwise. The wiring harness really just seems to activate the plunger which seals the canister and the pump motor which I assume is what evacuates the canister to purge it. I took out my DC power supply to test this. Tried it at 5V and the motor had a slight hum but didn't seem to do anything. Cranked it to 12V and same thing. The plunger on the right definitely opens and closes when I apply voltage. Went back to the motor and after I left it connected for maybe 10 seconds I hear it click in and spin like it's supposed to.

Note that I don't know what the voltage to this should be. The FSM doesn't saw, and the Electrical Wiring Diagram only indicates it's receiving voltage from the ECM.

 

[linuxgod]

If anyone has a fouled charcoal canister and wants to try mine, I have a strong suspicion my canister was fine but the pump was bad. I’d be happy to send my canister (sans pump) to someone for the cost of postage if you wanted to swap your pump into it.

If you’re not sure if the canister or the pump is bad, you can run the evap tests in techstream, and there are options to activate the pump. Activate it and climb under the truck and listen for it - if you can hear the pump motor purging but you’re still getting codes then the pump is ok and the canister is bad. If you can’t hear the pump then my canister probably won’t help.

I am questioning how the pump died in less than a year though. I mean I do off-road and I’m sure it got dunked briefly at some point, but there’s size to signs of water infiltration in this unit, despite what the dealer claimed. I may try to crack it apart further just for pics for the forum to analyze. New replacements seem to be about $200 on eBay, $300 through a dealer, and since you can’t get a charcoal canister without one unless you’re sure only your pump is bad it seems unwise to just swap that if you have a CC that’s many years old anyway.

 

[prharper]

If anyone has a fouled charcoal canister and wants to try mine, I have a strong suspicion my canister was fine but the pump was bad. I’d be happy to send my canister (sans pump) to someone for the cost of postage if you wanted to swap your pump into it.

If you’re not sure if the canister or the pump is bad, you can run the evap tests in techstream, and there are options to activate the pump. Activate it and climb under the truck and listen for it - if you can hear the pump motor purging but you’re still getting codes then the pump is ok and the canister is bad. If you can’t hear the pump then my canister probably won’t help.

I am questioning how the pump died in less than a year though. I mean I do off-road and I’m sure it got dunked briefly at some point, but there’s size to signs of water infiltration in this unit, despite what the dealer claimed. I may try to crack it apart further just for pics for the forum to analyze. New replacements seem to be about $200 on eBay, $300 through a dealer, and since you can’t get a charcoal canister without one unless you’re sure only your pump is bad it seems unwise to just swap that if you have a CC that’s many years old anyway.

Great info Geoff!

 

[CruiserReady]

Are you all seeing these codes hearing a gurgling at shut off when hot? I haven't had the P0441 code for a year or so, but have gurgling/bubbling sounds when I initially turn off the truck when it's really hot (Las Vegas). About 50% of the time I do get some fuel smell in the garage.

Never replaced any parts, tempted to throw a gas cap at it. But I assume my canister is full of fuel?

Just finding this thread now. I've been having this code on and off for several years. I am also in Vegas and I occasionally get gurgling which I would assume is fuel boiling. Lately this has gotten so bad that sometimes I cannot fuel at a gas station because there is so much pressure that it pushes the incoming fuel back out. I figured a new vsv and cannister would fix this but this thread has me doubting that. At this point this seems like a fire hazard so it's pretty high priority for me.

 

[prwillard2]

Anybody know how many miles/cycles it takes to clear a permanent P0441 code? I had 2 instances of the CEL with only a P0441 code last weekend in Utah. Cleared both times and have driven over 600 miles and many starts since last clearing it and the permanent P0441 still resides. I scan every time I drive and haven't had any further current codes and dont think any pending either so I have no idea why the permanent one remains. I suppose I'll get the techstream laptop out and try to run the active tests, but the evap monitors I brought up on my OBD fusion seem to indicate the VSV is cycling properly. I have no idea what the expected flow is at any condition but when the VSV goes from off to on you see the actual purge flow go from 0 to some positive number. I will say I have boiled gas at least a couple times since last canister replacement so maybe its shot again.

Mine lasted nearly 2 weeks before it just "went away" after constantly clearing the code. Not sure if my canister dried out from the boiled fuel that got into it, but I only ran about 60% capacity in my aux tank and would only fill my main tank after getting to under 1/4 of a tank left.

Typically would get the P0441 code after filling up my main tank completely and figured I would have to constantly clear the code every 3 or 4 start ups in perpetuity until I replaced the canisister.

Now it's been more than 2 weeks and haven't gotten the code despite filling my aux tank all the way and filling my main tank to full as well.

Coastal NC temps (~mid 90's) with high humidity for reference.

Got the boiling fuel in Utah (temps in ~110's) while traveling cross country as part of my move in July.

 

[LvCruiserNewb]

Mine lasted nearly 2 weeks before it just "went away" after constantly clearing the code. Not sure if my canister dried out from the boiled fuel that got into it, but I only ran about 60% capacity in my aux tank and would only fill my main tank after getting to under 1/4 of a tank left.

Typically would get the P0441 code after filling up my main tank completely and figured I would have to constantly clear the code every 3 or 4 start ups in perpetuity until I replaced the canisister.

Now it's been more than 2 weeks and haven't gotten the code despite filling my aux tank all the way and filling my main tank to full as well.

Coastal NC temps (~mid 90's) with high humidity for reference.

Got the boiling fuel in Utah (temps in ~110's) while traveling cross country as part of my move in July.

My permanent code is still resident a month and about 800 miles later. Havent gotten any current faults or CEL's since the utah trip though. I think its too hot here to complete the active test to clear the permanent fault. Gonna wait till it cools down enough to get fuel tank under 95 degrees for a few days and run the active test in techstream and see what happens. Otherwise I just ordered a new canister and VSV's on the current 25% off parts sale to put in now or save for later should it get worse.