Evaporative System Codes P043E, P043F, P2401, P2402, P2419.

So my 2010 Gen 3 just turned over 200,000 miles the other day. I went to my usual Costco that I have been stopping at twice a week for the last 14 years to fuel up. I have never had issues getting fuel into the tank, but today it kept stopping after accepting a gallon or so. I moved to another pump, but it acted the same way. I got the car fueled up, and made a mental note of the problem. Yesterday when starting the vehicle after sitting all day at work the check engine light stayed on. This is the first time I have had a check engine light in 200K miles. My scan gauge indicated codes P043E, P043F, P2401, P2402 and P2419. I wrote down all codes and cleared them. The next morning after sitting all night I checked codes again, no light yet, but all the same codes are pending again.
Google searching today comes up with quite a few hits for this collection of codes, all pertaining to an issue with the evaporative emissions system. I was a career mechanic with GM for 16 years and had 5 years or so of the enhanced emission system fun before I left the trade. I am suspecting an issue with the charcoal canister and its associated devices including the vent valve, and vacuum pump. Based on past experience and reading I am aware that the vehicle runs an evaporative system test to check for leaks and system integrity after the vehicle has been off for approximately 5 hours. I am planning to purchase a used part on Ebay soon and then get the car on my rack to perform any diagnostics I can. In all my google searching most hits were for other Toyota models, but I thought I would check the forum here and see if anyone with a Gen 3 has encountered this issue yet. Any feedback would be appreciated.

 

If anyone is following this thread, or maybe it will help someone in the future. Since the original flagging of this code I have not seen the check engine light again and no pending codes have showed up. I have been through at least 5-6 drive cycles that should have resulted in time for this test to run after 5 hours of sitting. But I was still having issues putting fuel in the vehicle. So this weekend I got the car up on my rack and pulled the evap canister down. I performed tests from my manual to verify that:
The vent valve operates properly when energized.
The purge vacuum pump runs when energized.
The path through the canister is clear and air passes to the proper areas when pressurized.
What I did find it that there was quite a bit of water in the canister filter and the canister pump module. The water in the canister filter had saturated the cotton filter material and made it difficult to blow through the filter. I dried out the filter and blew all the water out of the filter and pump module and put everything back together. I will find out next week if that fixes the issue of difficulty adding fuel. I am not sure how the water got in where it does not belong, but here in California we have had a ton of rain and a lot of roads I drive have been partially flooded so I can only think that played a part in it.

 

Wetback1, if you would like to send me an email to my account, [email protected] I will make contact with you and provide my phone number as I can tell you what I found. The problem occurred again late in 2016 with the first real amount of rain we had here in California. I would love to describe the repair here but it is pretty complex.

 

Grid, I will do my best, but its late tonight and I will need a few hours to get all the details into a response.

 

So Wetback1 here is a semi brief description of the issue. The problem started in early 2017 according to my first post which was the first time California had any normal rainfall since I had purchased the car. The issue with the codes and inability to fuel the car were due to the water getting into the evaporative system. Once I removed the canister and removed all the water all the codes stayed cleared and I was able to fuel the car normally.
The problem re-occurred in late 2017(I put 2016 in my last post, my mistake) after the rainy season started. I pulled the canister and again found water in the canister. I started tracing out the system for the vent as I assumed that had to be how the water was getting in. I found the canister is vented to an airbox behind the LR corner of the bumper, and then connects to a hose that routes to the top of the fuel filler neck. Wrapped around the top of the filler neck is a plastic housing that allows air in at the top of the filler neck, and also has a couple of small holes at the bottom of the same assembly to drain water.

Around and under the filler neck is a rock shield that I removed. It is #9 in the snip below.

When I removed the rock shield it was full of dirt and gravel. I drive a lot on dirt roads, and roads in the winter that are sanded or graveled for snow and ice. When I removed the rock shield it did not even occur to me that the amount of dirt and gravel was blocking the drain holes for the vent assembly. After I blew out the vent assembly and made sure the drain holes were clear I put the gravel shield back on. It was then I figured out that all that dirt and gravel was blocking the drain holes, and forcing the rain water into the vent line and eventually into the canister.
So the short story is if you find water in the canister assembly you will need to dry it out.
Once cleaned check the vent system for any broken or damaged lines.
Then remove the rock shield and look for large amounts of debris that could be blocking the drain holes and forcing water into the evap vent system. Hope this helps you or anyone else.
I have a good friend who has worked for Toyota for 15+ years and is awesome. He had never seen this issue before when I had contacted him. Possibly because he works in a large metropolitan area and most of those vehicles travel asphalt roads.

 

Matt, if you did not take the canister apart then there may still be water inhibiting flow. There is a fabric filter of some kind in the canister that was saturated with water in my case. It may dry out over time if given the chance. You can PM me if you want. I had purchased a canister as a spare and have no need for it now that I sold the 2010.

 

Hi Tacopyro, this may be an option if you have the equipment. I was able to get my canister dry without cutting it up. I was able to use compressed air to blow out the filter and then give it overnight to dry out. But your idea about a vacuum chamber is very interesting.

 

Sliman, the canister is under the car, just in front of the fuel tank. You need the vehicle on a rack or safely supported with jack stands. There are not any detailed instructions for disassembling the canister since Toyota doesn't really expect it to be serviced. But if you have a reasonable mechanical aptitude I think you can figure out how to remove the canister and carefully remove the parts needed to access the fabric filter and dry out the canister. Also look at the other snips that are part of the post to look at the rock shield that is causing the issue. Please write back if you have other questions. Sorry I do not have a manual to share.

 

Hi sliman, the pictures you sent of Toyota 77746-47010 are of the "Vapor Canister". I would say that it should not be cracked, so getting that fixed is important. But there is no filter in there as I recall, it is just a plastic box of air. Once you get this handled you need to be looking at the evaporative canister which should be in front of the fuel tank and looks like the snip I sent. Much bigger and heavier, more hoses and wires attached. As far as removing the hoses you should be able to use a small screwdriver to help get the clips to push back out of the way while you are pushing the tabs to release it from the canister.