Anatomy of P0456 - Small Evap Leak (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

spaber05 said:
Much appreciated @TeCKis300 - Assuming I'm not doing any real harm to the engine I might just punt this until the light becomes more constant and then do the high loop at the same time. Just disappointed this is happening in a practically new Cruiser! Also, I'm assuming none of this is covered under any kind of warranty, correct (assuming all of the above is needed)?
Click to expand...

Sure, you can try warranty, but the moment they get in there to fix it, they will be have to deal with the LRA front and center, and realize the system is modified.

If you're situation is intermittent enough and corrosion is minimal, you can try spraying down the breather hose with WD-40 to remove as much water as possible. Also high-loop it while you're in there. In rainy regions, the water ingress can be significant.
 
Seeing this at the top of the 200 zone, I must post an update: Assuming that the CC is vulnerable to failure in several ways (H2O ingress, tank overfill, vapor overwhelm fouling, valve failure, etc.), I decided to reclassify the part as a consumable. Since the 'correct' part is $350-$650 (depending on source and included accessories), I decided to experiment a little. This is an off-brand (yes, yes, I know) CC for a Toyota Corolla at sub-$200. This has been installed on the 200 since ~September '23, and works like a charm.

Granted, I've taken and take as many of the precautions and best practices of the MUDhive mind on this topic, but replacement will sting a little less, should that become necessary. (Don't forget to clean your radiator)
 
TeCKis300 said:
Sure, you can try warranty, but the moment they get in there to fix it, they will be have to deal with the LRA front and center, and realize the system is modified.

If you're situation is intermittent enough and corrosion is minimal, you can try spraying down the breather hose with WD-40 to remove as much water as possible. Also high-loop it while you're in there. In rainy regions, the water ingress can be significant.
Click to expand...
I'm lucky in that the dealership I see regularly seems to be more "mod-friendly" than most so I have some confidence that they might find a way to honor the warranty, but we'll see. I'll attempt the WD40 idea, hadn't thought of that
 
I havent touched mine yet but i posted three years ago about gas cut off on fill up and thought it was the neck. I have made sure not to even remotely overfill it since then and it’s only happened once or twice. Seems to only happen when the weather changes and gas must not be swapped yet. Should i be worried? In the beginning it literally would not fill, so im wondering now what the true cause could be.
 
This is a great thread and I booked marked it for the day I would experience P0456. Today is the day.

IMG_4490.jpg

At least having the always running OBD Fusion app on the head unit is handy. Flashing 4LO and CEL good morning greeting. Drove into work with the blinking lights as I wanted to reread this thread before clearing the codes. I'm not convinced this is due to my LRA as its only been in for 3000 miles or so. it still could be of course if I have something loose causing the "very small leak". For now, I'll just reset codes and see how frequent it comes back.

Also not sure what P1604 is, though I just replaced the battery and it did the fire up and die thing which it always does when I disconnect the starter battery. I just never noticed a code before.
 
I get that code (occasionally) .. after I replaced the canister. For now it been clear code vs a smoke test.
 
@TeCKis300 you have all kinds of threads on this topic and have been very helpful. I put the Insulation on my holiday gift list for a winter project. I want to avoid the boiling fuel as I knoww that isnt good for the Evap canister.

I am getting the same codes you had
  • P043E catalyst temperature sensor circuit low (bank 2 sensor 2).
  • P043F catalyst temperature sensor circuit high (bank 2 sensor 2)
  • P2401evaporative emission system leak detection pump control circuit low.
  • P2402 evaporative emission system leak detection pump control circuit high.
  • P2419 evaporative emission system switching valve control circuit low.
I wanted to try the easy stuff first.
I replaced the Charcoal Filter
Switched to the recommended Evap filter and hose.
I replaced the Vacuum Switch Valve on top of the engine
I replaced the Gas Cap
I have been running Non Ethanol fuel

And still I had the same codes today along with the 4LO dash light.

Since I can reset this, not an urgent problem, but I would like to fix it and replace The Evap Canister over the Aux Tank

Thinking through the steps in my mind
  1. Remove the spare underneath tire
  2. Remove the Spare tire holder
  3. Drain the Aux Tank
  4. Through the passenger rear wheel well, disconnect the the hose from the Fuel filler tube (Correct?) Any other hoses or things disconnected from here?
  5. Use a floor jack to support the tank while removing the mounting bolts. Any tips here?
  6. Take a beer and cigar break
  7. Slowly lower the tank- Guessing I need to remove the line from this tank to the pump??? This step or before lowering tank?
  8. Anything else to watch for while removing the tank?
Now I am ASSUMING that I will have full access to the Evap Canister and I can replace it and reverse thee steps to re-install the tank.

Apppreciate any thoughts, suggestions or clarifications from you and anyone else that has done this. My problems always come from hitting a step that isn't clear or obvious to me. I sometimes spend a lot of time and smack myself once I figure it out. On rare ocassions I have created an additional area needing repair :)
 
Romer said:
@TeCKis300 you have all kinds of threads on this topic and have been very helpful. I put the Insulation on my holiday gift list for a winter project. I want to avoid the boiling fuel as I knoww that isnt good for the Evap canister.

I am getting the same codes you had
  • P043E catalyst temperature sensor circuit low (bank 2 sensor 2).
  • P043F catalyst temperature sensor circuit high (bank 2 sensor 2)
  • P2401evaporative emission system leak detection pump control circuit low.
  • P2402 evaporative emission system leak detection pump control circuit high.
  • P2419 evaporative emission system switching valve control circuit low.
I wanted to try the easy stuff first.
I replaced the Charcoal Filter
Switched to the recommended Evap filter and hose.
I replaced the Vacuum Switch Valve on top of the engine
I replaced the Gas Cap
I have been running Non Ethanol fuel

And still I had the same codes today along with the 4LO dash light.

Since I can reset this, not an urgent problem, but I would like to fix it and replace The Evap Canister over the Aux Tank

Thinking through the steps in my mind
  1. Remove the spare underneath tire
  2. Remove the Spare tire holder
  3. Drain the Aux Tank
  4. Through the passenger rear wheel well, disconnect the the hose from the Fuel filler tube (Correct?) Any other hoses or things disconnected from here?
  5. Use a floor jack to support the tank while removing the mounting bolts. Any tips here?
  6. Take a beer and cigar break
  7. Slowly lower the tank- Guessing I need to remove the line from this tank to the pump??? This step or before lowering tank?
  8. Anything else to watch for while removing the tank?
Now I am ASSUMING that I will have full access to the Evap Canister and I can replace it and reverse thee steps to re-install the tank.

Apppreciate any thoughts, suggestions or clarifications from you and anyone else that has done this. My problems always come from hitting a step that isn't clear or obvious to me. I sometimes spend a lot of time and smack myself once I figure it out. On rare ocassions I have created an additional area needing repair :)
Click to expand...
Good plan Ken. My evap codes have stayed away but I'm confident they will surface again at some point. Have a new charcoal canister and have some of the same questions about dropping the LRA tank to get to it. Watching this thread.
 
Romer said:
@TeCKis300 you have all kinds of threads on this topic and have been very helpful. I put the Insulation on my holiday gift list for a winter project. I want to avoid the boiling fuel as I knoww that isnt good for the Evap canister.

I am getting the same codes you had
  • P043E catalyst temperature sensor circuit low (bank 2 sensor 2).
  • P043F catalyst temperature sensor circuit high (bank 2 sensor 2)
  • P2401evaporative emission system leak detection pump control circuit low.
  • P2402 evaporative emission system leak detection pump control circuit high.
  • P2419 evaporative emission system switching valve control circuit low.
I wanted to try the easy stuff first.
I replaced the Charcoal Filter
Switched to the recommended Evap filter and hose.
I replaced the Vacuum Switch Valve on top of the engine
I replaced the Gas Cap
I have been running Non Ethanol fuel

And still I had the same codes today along with the 4LO dash light.

Since I can reset this, not an urgent problem, but I would like to fix it and replace The Evap Canister over the Aux Tank

Thinking through the steps in my mind
  1. Remove the spare underneath tire
  2. Remove the Spare tire holder
  3. Drain the Aux Tank
  4. Through the passenger rear wheel well, disconnect the the hose from the Fuel filler tube (Correct?) Any other hoses or things disconnected from here?
  5. Use a floor jack to support the tank while removing the mounting bolts. Any tips here?
  6. Take a beer and cigar break
  7. Slowly lower the tank- Guessing I need to remove the line from this tank to the pump??? This step or before lowering tank?
  8. Anything else to watch for while removing the tank?
Now I am ASSUMING that I will have full access to the Evap Canister and I can replace it and reverse thee steps to re-install the tank.

Apppreciate any thoughts, suggestions or clarifications from you and anyone else that has done this. My problems always come from hitting a step that isn't clear or obvious to me. I sometimes spend a lot of time and smack myself once I figure it out. On rare ocassions I have created an additional area needing repair :)
Click to expand...
Needs more cigar and beer breaks. Don't forget two hidden wires on top of tank. Check tank installation and compare to most recent docs from LRA. Why not pull main tank while you're down there and replace fuel pump. (Account for additional cigars/beer.)
 
Ken, I installed my own LRA tank, and your plan is solid. Of course, drain the tank first. There are two hoses you can remove from below - I seem to recall that they are the fill hose and the hose that goes to the fuel pump. Disconnect sender wires before dropping the tank too far. I would recommend using a hydraulic lift table, floor jack or transmission jack to drop it in a controlled fashion, the tanks are reasonably heavy. This will give you full access to the charcoal canister. Installation is a little bit of a pain, but the assistive lifts or a helper will make it easy. I did mine solo and wouldn't recommend it.
 
isthatalexus said:
Needs more cigar and beer breaks. Don't forget two hidden wires on top of tank. Check tank installation and compare to most recent docs from LRA. Why not pull main tank while you're down there and replace fuel pump. (Account for additional cigars/beer.)
Click to expand...
My fuel pump in the main tank was replaced via a Recall 3-4 years ago, so no need to do that.
 
CharlieS said:
Ken, I installed my own LRA tank, and your plan is solid. Of course, drain the tank first. There are two hoses you can remove from below - I seem to recall that they are the fill hose and the hose that goes to the fuel pump. Disconnect sender wires before dropping the tank too far. I would recommend using a hydraulic lift table, floor jack or transmission jack to drop it in a controlled fashion, the tanks are reasonably heavy. This will give you full access to the charcoal canister. Installation is a little bit of a pain, but the assistive lifts or a helper will make it easy. I did mine solo and wouldn't recommend it.
Click to expand...
Great suggestion on the jack. I have a Badlands floor jack. Removing and reinstalling skid plates it has worked, but always gets akward getting it on the jack or moving it off.

This looks like it would be good for the tank and skid plates

 
Romer said:
Great suggestion on the jack. I have a Badlands floor jack. Removing and reinstalling skid plates it has worked, but always gets akward getting it on the jack or moving it off.

This looks like it would be good for the tank and skid plates

Click to expand...
For re-installing my skids, I use this Harbor Freight transmission jack and it works great. This is what I plan to use when I lower my LRA.
 
Romer said:
looks nice. Is it tall enough at 23" max lift? I haven't measured but seems higher than that
Click to expand...
I just removed and reinstalled my skids with the truck on ramps and that HF jack had no problem getting the skids flush to the frame. The LRA does sit higher so it's a good question if its got enough reach.
 
Getting ready for the Evap canister and thought I would pull off the spare tire (I have two) and tire carrier. Need to clean and lube the spare tire carrier, it was real hard getting down

Got 2 of the 4 bolts off for the tire carrier. Started one which seems easy. the 4th got started and then got hard and it is an akward spot for tools. Passenger side right against the tank. Any tips on tools or other that folks have used here?

Also, once all 4 bolts are off, looks like it is in there tight. Any suggestion on how you worked it out?

Thanks in Advance
 
Romer said:
Getting ready for the Evap canister and thought I would pull off the spare tire (I have two) and tire carrier. Need to clean and lube the spare tire carrier, it was real hard getting down

Got 2 of the 4 bolts off for the tire carrier. Started one which seems easy. the 4th got started and then got hard and it is an akward spot for tools. Passenger side right against the tank. Any tips on tools or other that folks have used here?

Also, once all 4 bolts are off, looks like it is in there tight. Any suggestion on how you worked it out?

Thanks in Advance
Click to expand...
I had to hit a couple of bolts with PB Blaster to get them off

I couldn't get the Spare tire carrier off though and decided I needed to take off the two brackets the carrier bolts in to.

The Resonator was in the way so I performed a mod I was planning on doing later and cut off the resonator. After I get this completed, I will go to a muffler shop and have theem build a pipe going out behind the spare tire. This mod will likely help with not overheating the aux tank.

With the brackets removed, I was able to get the carrier off.

The Evap canister comes tomorrow, but will wait until next week to replace it as I don't want to risk the truck being down as I need the 200 to make an airport run on Saturday. Maybe when I get this all done I will start a sperate thread on removing the Aux tank, but wanted to add progress here for completness
 
Ken - you must have the 12gal LRA. Didn’t Slee install that for you ?
If so, I heard they don’t install that size LRA anymore.
Be great if you could do a write-up of the charcoal canister replacement too.
 
Some thoughts I felt worth discussing since this is the P0456 small leak thread

I had multiple EVAP codes that lead me to replace my Evap/Carbon canister I disscused in the other thread

P0456 was not one of them. My filter on the breather was also clogged and I replaced that

Driving several days I just got a P0456 code for small leak, the rest of thee codes are gone. I tightened (3 clicks) up the gas cap, was only 1 click. Also several hose clamps could use more tightening which I did today. There is one I have to take the wheel well cover off that I will address if it comes back.

Edit: I also has a small leak at the drain plug which I didn't see until the next day. Tightened the plug up and leak stopped. I am always afraid of overtightening and stripping/breaking a bolt.

Thinking about the canister, there are 3 hoses connected. The only one I would be concerned about having a loose connection because of the design is the one that goes to the Carbon filter and then out to the vent. Note the hose on the bottom clamp was adjusted better after this picture. Also, note from the other thread the connector over the support bar which is what broke and why I had to drop the tank again to repair, but that is a story for the other thread.
1735084588257.png


Based on what I read and thinking about the test that looks for small leaks, I BELIEVE (please shoot darts) that this code occurs if there is a small leak from the Evap Canister to the fuel system (Fuel lines, Tank Vents, Canister) and NOT from the Evap canister out to the Carbon filter and vent for air. The test pressurizes the fuel system and looks to see if the pressure slowly degrades over time. This video was helpful


In it he pressurizes the stand alone canister and opens the valve and watches the pressure maintain. He states that if it slowly degrades, it would set the leak code. Since the circled connector passes vapor out through the Carbon filter and then to the air filter, I am theorizing this can't be the cause of the leak.

Thoughts on that? I think that would be an important distinction and remove part of the EVAP system as a cause which is helpful in troubleshooting issues

I believe I have taken care of it, but time well tell. I was thinking about this as I was looking at what to look at and thought I would share my thoughts here since my wife wasn't interested :)
 
Last edited:
You must log in or register to reply here.

Similar threads

kcjaz
How long can you keep just keep clearing P0456 code (Evap leak)
Replies
16
Views
2K
kcjaz
kcjaz
Romer
Removal of 12.5G LRA Tank for replacement of Evap Canister
2 3
Replies
52
Views
6K
Romer
Romer
N
Valley Plate Leak?
2
Replies
29
Views
1K
nicoparren
N
OldCarSmell
LRA Aux leak?
Replies
5
Views
445
OldCarSmell
OldCarSmell

Users who are viewing this thread

Total: 2 (members: 0, guests: 2)

Share this page

Back
Top Bottom