Removal of 12.5G LRA Tank for replacement of Evap Canister

[Romer]

Still tracing down a small leak. P0456

I do not see a pending or set code for the P0441 and I have cleared the pending for the P0456 several times. The P0441 is only permenant. All the original permenant codes have cleared. Should I pursure the P0441 or since it is only permemant code ignore it? May be a residual from the install?

I have one of the older tanks from 2018 @wardharris and I may have the clearance issue. Not sure how to tell. Wondering if some how the new canister was damaged, but then I am thinking I would get more than the P0456 very small leak code. I still have a few things to do before I look at dropping the tank. I would live with it, but guessing Colorado emissions won't pass with that code

 

[TeCKis300]

Still tracing down a small leak. P0456

I do not see a pending or set code for the P0441 and I have cleared the pending for the P0456 several times. The P0441 is only permenant. All the original permenant codes have cleared. Should I pursure the P0441 or since it is only permemant code ignore it? May be a residual from the install?

I have one of the older tanks from 2018 @wardharris and I may have the clearance issue. Not sure how to tell. Wondering if some how the new canister was damaged, but then I am thinking I would get more than the P0456 very small leak code. I still have a few things to do before I look at dropping the tank. I would live with it, but guessing Colorado emissions won't pass with that code

View attachment 3800623

There definitely is a clearance issue in the early 12.5 gallon tanks. It'll pretty much pinch the charcoal canister between the tank and the frame unless you remount it in the way that puts it tighter against the cab. I had this documented in my original install thread.

Both codes can be triggered in slightly different ways, but a common root issue to both suggests there is a leak somewhere. Is there a way you can pressure test the system or smoke test it?

 

[Romer]

There definitely is a clearance issue in the early 12.5 gallon tanks. It'll pretty much pinch the charcoal canister between the tank and the frame unless you remount it in the way that puts it tighter against the cab. I had this documented in my original install thread.

Both codes can be triggered in slightly different ways, but a common root issue to both suggests there is a leak somewhere. Is there a way you can pressure test the system or smoke test it?

I was reading that today. I will work on putting something in there. Slee had a round plastic dish on top of the tank, I thought maybe the just left it there

On the code question. I tightened one loose clamp and have two more things to check if that doesn't clear it up. Have to drive enough for the test to run overnight for results. There is no instant gratifification troubleshooting this

My question was since the P0441 was only a permenant code with no SET or PENDING codes, does this mean it is history and not a current issue to worry about? Did it get fixed so the set one went away but havent driven enough to clear the permenant one?

 

[Romer]

reworked a few suspect hoses with no change

I removed the Aux tank and capped the Fuel fill tube, the Vent hose and the fuel transfer hose to work through this issue without the tank and drove 25 miles yetsreday. The realtime diagnostics revealed no issues. The Evap test hasnt run since yesterday so drove it more today. Hopefully, this method will work to help resolve the issue.

looking at @TeCKis300 install thread to understand clearance issues since mine is one of tyhe original 6 tanks with the older design. I did notice noises when I put the tank back in that are gone without the tank. Now I know why there was a peice of plastic on top of the tank when I removed it.

 

[TeCKis300]

reworked a few suspect hoses with no change

I removed the Aux tank and capped the Fuel fill tube, the Vent hose and the fuel transfer hose to work through this issue without the tank and drove 25 miles yetsreday. The realtime diagnostics revealed no issues. The Evap test hasnt run since yesterday so drove it more today. Hopefully, this method will work to help resolve the issue.

looking at @TeCKis300 install thread to understand clearance issues since mine is one of tyhe original 6 tanks with the older design. I did notice noises when I put the tank back in that are gone without the tank. Now I know why there was a peice of plastic on top of the tank when I removed it.

Reworking the mounting so the charcoal canister is tighter against the body is a bit of a PITA, but necessary with these early tanks. If you're so inclined and your build takes you this way, doing a body lift now from NST Spec - https://nstspec.com/ will also solve this problem nicely.

 

[Romer]

Reworking the mounting so the charcoal canister is tighter against the body is a bit of a PITA, but necessary with these early tanks. If you're so inclined and your build takes you this way, doing a body lift now from NST Spec - https://nstspec.com/ will also solve this problem nicely.

I appreciate that, but think I will pass on the body lift

I have a question though. My Canister looks different than yours. It looks the same as the one I took off

I thought the connector circled went to the carbon filter and then out, but that is the big hose on the bottom. That is why I wasn't that concerned with it fitting that well. I may have mangled it a bit getting the clipout

So it must either come from the tank or the purge valve (Vacuum switching valve). Wouldnt a leak here set the P0456?

I was thinking of ways to try and test this by Taping it? Wrapping it with plastic or ???

an article I read on Toyota EVAP systems came with this diagram

 

[Romer]

here is a good diagram from the repair manual. Looks like the vent line from the fuel tank #5

 

[Romer]

looking through the description of how a Toyota system works for the off key test, a leak here makes sense in an error. What I read says after 5 hours and all other criteria is met, the vehicle will run its off key EVAP test. It will close the vent valve, which is the hose from the canistsre to the filter and air. It will turn on the pump and pressurize the system and look for maintaining pressure over a period of time. A leak anywhwer in what is pressurized could cause my issue. This includes the Fill neck, gas tank, purge (Vacuum) valve Canister or any hoses in between

So not pretty. I wrapped with clingplastic wrap, Blacl electrical tape, zip tie around bottom then another layer of plastic wrap and another layer of tape.

Too bad it takes so long after I drive to get it to start the test. Results hopefully tomorrow

 

[FerrisBueller]

The one you circled in the photo is the vapor hose that goes directly to the main fuel tank, and if I remember correctly, it's like $50 from Toyota (so not too bad to replace). It's very accessible to get to the other end of that hose, which is another similar green-clip connector about half way between the diff and the edge of the fuel tank. I've circled the two ends of the same hose in this photo.

 

[FerrisBueller]

Also, in your photo, it looks like the hose connector is not fully seated (not sure if that's because of the mangled clip?) There should be about half that gap between the connector and the canister body. It resisted a lot when pushing the connector on all the way on mine.

 

[FerrisBueller]

Oh, I happened to already have a photo with a tape measure conveniently placed right next to that connector

Looks like it should be about 5/16" gap.

 

[Romer]

Thanks! Do you have a part number for that harness?

I will see how the test results are and if pass go get emission tested a month early. Then I will look at seating that connector better to see if that works.

I have learned more about Toyota Evap systems than I care to. Time to go for another drive. At least recently, it has taken two warm up cycles to initiate the test. I let it sit in the driveway for two hours to cool down

 

[TeCKis300]

I appreciate that, but think I will pass on the body lift

I have a question though. My Canister looks different than yours. It looks the same as the one I took off

I thought the connector circled went to the carbon filter and then out, but that is the big hose on the bottom. That is why I wasn't that concerned with it fitting that well. I may have mangled it a bit getting the clipout

So it must either come from the tank or the purge valve (Vacuum switching valve). Wouldnt a leak here set the P0456?

I was thinking of ways to try and test this by Taping it? Wrapping it with plastic or ???



View attachment 3805781


an article I read on Toyota EVAP systems came with this diagram
View attachment 3805786

I'm on a trip at the moment so don't have my full references to help troubleshoot. Keep at it though!

 

[FerrisBueller]

Thanks! Do you have a part number for that harness?

The part number for the hose that I had purchased is 77404-60050 (but might be different per model year, of course). $52 from Fred Anderson Toyota:
Fuel Tank Vent Hose Sub-Assembly #77404-60050 | Autoparts.toyota.com - https://autoparts.fredandersontoyota.com/products/product/hose-sub-assy-fuel-7740460050

 

[Romer]

The part number for the hose that I had purchased is 77404-60050 (but might be different per model year, of course). $52 from Fred Anderson Toyota:
Fuel Tank Vent Hose Sub-Assembly #77404-60050 | Autoparts.toyota.com - https://autoparts.fredandersontoyota.com/products/product/hose-sub-assy-fuel-7740460050

looks like it is a different one. Did it come with the green clips, at least for your year.

Thanks for posting the location of the other end and how accessable it is. Since I didn't know that this requires a lot of force, anything special with the other end?

 

[Romer]

likely not 1:1 but this shows mine isnt fully seated like yours.

 

[FerrisBueller]

Yes, it came with the green clips already installed. You can treat the clips as being captive (the clips only need to slide out part way to allow the hose to disconnect). I wouldn't really say it's a lot of force to reconnect / fully seat the hose, but more of being deliberate rotating it back and forth while pushing on it.

For the other end of the hose, at least on mine, it's exactly the same type of connection. Just slide the green clip partially, then pull the hose to remove. Then twist & push the hose to reinstall, followed by sliding the clip the rest of the way back in.

 

[FerrisBueller]

There are a couple plastic c-shaped brackets that route the hose along the body, but the hose should easily pull out & away from those brackets just by pulling on it.

 

[BIC JET]

I ran the 12.5 gallon LRA tank dry then drove 300 miles without putting any gas in it. After that, the codes all washed out, filled her back up and no issues further.

 

[Romer]

woohoo, after 3 days of driving different profiles the test finally ran and the EVAP test passed in the report.

Cause was the not fully seated Fuel tank to Canister vent tube

All temp and permenant codes are gone. No issues reported

I will have to run the EVAP test again when I put the tank in.

I did order this on Amazon as it has more capability than my phone OBD program. It says it can kick off EVAP tests and is setup for Toyotas so will work for the 200 and the Tacoma. Had several really good reviews, but none that actuially ran the test

https://www.amazon.com/dp/B0D626T9HK?ref=ppx_yo2ov_dt_b_fed_asin_title

I will post up after I reinstall the tank. The rubber strips will be here in a week so it will be after that