Toyota Po441, P0446 EVAP Vacuum Switching Valve VSV Testing and Canister Replacement

[chapshow1]

Thanks, I must have gotten lost in my search for EGR valves and came across this video. As you can tell, it's all Greek to me anyway, but I try to understand what I can about my car.

[chapshow1]

I just had my egr valve cleaned out. They said it was very dirty. They cleared the code and so far (3 days) no check engine light. I got online here to learn more about the egr and I am wondering if I should expect the VSV valve to be going out pretty soon. They said they checked everything down the line, (but I didnt see the car in the air at all, so I'm pretty sure they didn't mean that they checked the canister). Its a 95 v6 Camry with 190000 miles.

[markjhicks]

@chapshow1 The EGR and EVAP are two separate systems. If you have problems with the EGR valve there is no reason to think you will have problems with the VSV. If you have any other concerns please let me know,

Mark Hicks

Wells Vehicle Electronics

[mcleod2]

thank u

[mcleod2]

ok so i went to toyota and they said i need a new purge valve and canister. I dont want to buy the part from toyota, instead i want to get it from advance, they typically dont carry it in that title but they say they have a purge valve solenoid is this the same thing?

[markjhicks]

@mcleod2 The purge solenoid, I would think is the same as the purge valve. However, some manufacturers call out different names. I would check with whoever you are buying the part from to be sure.

Mark Hicks

Wells Vehicle Electronics

[xx217xx]

My 2001 Toyota Camry LE gave out codes P0440, P0441, P0446. I took out my canister and did the battery voltage test, and I heard the noise from the solenoid, so does that mean that the canister is still good? If it's still good, what may be causing the problem?

[markjhicks]

@xx217xx It means the solenoid is activating, but you still must make sure it holds and passes vacuum like it shows in the video. By far the most common cause for these codes on your vehicle are either a bad gas cap or canister. Here are some more instructions I hope will help you determine the anser to the problem:

1. Verify that the Vacuum Switching Valve (VSV) for the pressure sensor (located on the canister) operates correctly.

[markjhicks]

@markjhicks

This is a normally closed (N.C.) valve. When energized, it should open. When de-energized, an internal spring should close the valve.

2. Verify that the canister closed valve (located on the air filter housing) closes and does not stick closed when operated. This is a normally open (N.O.) valve. When it is grounded, it closes, and it should never stick closed.

[markjhicks]

@markjhicks

3. If both solenoids operate correctly and are not sticking, inspect for a restriction in the Evaporative Emission (EVAP) lines that could affect how the canister vents after a leak test is performed.

4. Verify that the fuel cap is a good seal. If the fuel cap leaks or does not hold the correct amount of vacuum when the system checks for a leak, all the codes will set.

Stay in touch

Mark Hicks

Wells Vehicle Electronics



[xx217xx]

@markjhicks Can the check engine light be intermittent? Because I scanned the car when the check engine light was on and turned the car off and unlugged it. I didn't delete the code. The next day I turned the car on to park in my garage to take the canister out, the check engine light wasn't on

[markjhicks]

@xx217xx Yes, it can happen and it is not unusual with an EVAP code. However, the code is still stored in the history even if the light goes out.

Mark Hicks

Wells Vehicle Electronics

[sidmalicious]

I replaced the cannister and the purge valve (in my driveway also - not hard at all). It still throws the codes. If i run it without the gas cap and them reset the ECM it runs fine and passes emissions. Then after a while it throws the codes, sputters, and sometimes dies in turns and at idle. Now, a new behavior of sputtering upon takeoff...reset the computer and it runs fine. What else should I check?

[markjhicks]

@sidmalicious I am a little lost, I help many people everyday, I am sorry I don't remember every vehicle. What is the year, make, model and engine size. Also what code(s) are being set?

Mark Hicks

Wells Vehicle Electronics

[sidmalicious]

@markjhicks 1999 Toyota Corolla CE 1.8l. P0446 & P0441.

[markjhicks]

@sidmalicious Chances are you will need to replace the charcoal canister with the VSV valve. But here is the test procedure if you would like to test it first:

:

1. Verify that the 3-way Vacuum Switching Valve (VSV) on the canister operates correctly. When the VSV is not grounded, the Fuel Tank Pressure (FTP) sensor should be connected to the canister side of the system only. When the VSV is grounded, the FTP sensor should monitor only the fuel tank.

Read first

Mark Hicks

Wells

[sidmalicious]

@markjhicks Um, yeah Mark - READ FIRST. I wasted $300 replacing the cannister, VSV works. Purge valve up front was bad, replaced, still throwing 446 & 441 codes. I pulled the ground off the battery again, and it drives fine, except the new sputtering upon takeoff. I'm going to change the auto transmission filter and fluid to see if that is why it sputters - it's past time to do that anyway, and it seems like it is in the wrong gear, like starting off in 2nd. I hope it's not the injectors.

[markjhicks]

@sidmalicious By sputtering, I will assume you are saying it is misfiring on acceleration. Your vehicle does have problems with injectors. But, be sure the ignition system is in good shape. Quick test for the injectors: if you can power brake and recreate the problem, have someone do that and you stand on the side of the vehicle ( not to get run over) then spray crab cleaner in the air intake and see if the problem goes away. If it does you have a fuel related problem.

Mark Hicks

Wells

[markjhicks]

@sidmalicious :

2. Monitor the FTP sensor and unplug the 3-way VSV and draw a vacuum into the canister and verify that it will hold vacuum and the FTP voltage will decrease.

3. Test and verify that the purge solenoid and wire harness are all OK. The purge solenoid should apply vacuum to the charcoal canister when grounded. Also verify that the hose from the purge solenoid to the charcoal canister does not leak.

Hope this helps you,

Mark Hicks

Wells Vehicle Electronics

[sidmalicious]

@markjhicks Everything tested good. Replaced injectors - still sputtering, but runs smoother after initial acceleration. :) Next venture is the fuel pump strainer. Oh, and now I have an exhaust smell in the cabin.

[xtwillox]

@sidmalicious

just a guess but maybe a clogged cat, mine did that after and replacement it ran like a top.

btw mine was a 97 avalon with v6 3.0

[sidmalicious]

@xtwillox Thanks. That's next, or at least donuts to make sure those aren't rotted.

[miked0071]

thanks you for the clip.....just did mine after looking for 2 weeks as to where it is on the car....was kinda a pain to replace in the driveway but after a cuple of hours it was all done

[miked0071]

@miked0071 also mine was a 2002 later model so geting the vsv not an otion had to replace the entire thing

[markjhicks]

@miked0071 You replaced it in the driveway ... Wow I am impressed, that is not an easy task at all! Nice work my friend!

Mark Hicks

Wells Vehicle Electronics

[jimmyismealright]

thank you for posting that video that made it easy for me to locate and replace it myself

[markjhicks]

@jimmyismealright Thank you for posting your experience. It was our pleasure to help you.

Mark Hicks

Wells Vehicle Electronics

[JUDGERAMBO]

How should the pressure sensor be tested?

[markjhicks]

@JUDGERAMBO If you are asking about this Toyota, you will need a scan tool to read the pressure then verify that the 3-way Vacuum Switching Valve (VSV) by the canister works correctly. When the 3-way VSV is grounded, the pressure sensor should read tank pressure. When the ground is taken away from the 3-way VSV, it should switch and allow the pressure sensor to check for vacuum in the canister.

I hope this answers your question,

Mark Hicks

[ikinner]

Great info! Thanks for the video - it made locating and understanding the whole system a breeze!

[markjhicks]

@ikinner Thank you for the kind words. It is our goal to accomplish just what you said, a better compliment could not be made.

Mark Hicks

Wells Vehicle Electronics

[ikinner]

Great info! Thanks for the video - it made locating and understanding the whole system a breeze!

[BobbyEnergy]

if that guy can shrink that small how come he didnt just do that and get up under the car to remove the cansister without having to waste time lifting the car up?

[2009jimmy2009]

happy until he gets the bill!

[markjhicks]

@2009jimmy2009 How many customers are happy when they get the bill? But you are right this is an expensive repair. It is a questionable design from the beginning. If the VSV was made to be replaced as a separate component the cost would drop dramatically.

Thanks for the comment.

Mark Hicks

Wells Vehicle Electronics

[Motocrossx23]

I'm currently running into this same code (P0446 and P0441) on my 1999 Toyota Corolla. I followed the steps and have the canister assembly out and on my bench. I tested the same way as in the video and no clicking sound. Is the canister the same as the Camry's? If I can replace the VSV instead of the whole assembly I'd rather do that.

[markjhicks]

@Motocrossx23 If you do not hear any clicking the solenoid is defective. If you can purchase the VSV separately than you can replace it. I dont think you can, but let me know how you make out on this one.

Mark Hicks

[lanzce80]

@markjhicks I replaced my charcoal canister and it took me 2 hours. I had a hard time removing one of the tubes. You're right, it's under the trunk, beside the fuel tank. Now I only need to reset the computer to get rid of the engine light. Thanks for the info.

[markjhicks]

@lanzce80 Hey good news! It always feels better after you have conquered a little of the unknown. Congrats!

Mark

[h23sirlude]

thanks for the video

[markjhicks]

@h23sirlude It is our pleasure! Thank you for viewing it. I wish you and yours a very Merry Christmas and a prosperous New Year.

Mark Hicks

Wells Vehicle Electronics

[lanzce80]

I have a 2007 Corolla and my engine light went off. Took it to a toyota dealer and found out that i need to replace my charcoal canister. I'm thinking of doing it myself because it would cost me a fortune to have them do it. Would the location be the same as the camry on the video? Thank you.

[markjhicks]

@lanzce80 I wish i had a direct answer for you...here is what i know. I have not changed one on 2007. I looked it up in AllData and in the location chart it shows the canister in the same area, under the trunk - near fuel tank. But the picture is not specific. I think it is easier than the one in the video, because the labor rate for replacement was only .5 hours. Please take a look in that area and let me know what you find.

Thank you and may you and yours have a wonderful holiday.

Mark Hicks

[CoolasIce2]

...be able to check the results right now , but I don't expect to get the same problem code.

[CoolasIce2]

UPDATE:

No parts stores list the VSV valve separately, but after hours of research, I found the part number of the VSV valve for my '99 Corolla. It is 90080-91240. It costs about $27 from internet dealers or $48 from local dealers.I disassembled the old valve, and it looks good, so I don't understand why it doesn't switch like it should. Even the resistance of 40 ohms is the same as the new valve, but it doesn't switch or click. I have a couple of other problems with my car, so wont be able...

[CoolasIce2]

The whole canister is over $250! Is there any way of replacing just the switch/valve?

[markjhicks]

@CoolasIce2 Unfortunately the VSV is integral to the canister. Not a very thoughtful design when it comes to replacement. But, there have been improvements to the original design and hopefully you will have to do this replacement only once. I wish I had better news for you, $250 is a lot of money to me too.

Mark Hicks

Wells Manufacturing L.P.

[EricTheCarGuy]

Nice work. I like the testing with a 9V battery off the car, makes it easy and accessible to most people.

[markjhicks]

@EricTheCarGuy Hey Eric, Thank you for the kind words. In fact a 9 volt battery can be used to do all kinds of testing. I know it is a secret, but I cant wait to see your new video!!

Mark Hicks

Wells Manufacturing L.P.

[EricTheCarGuy]

@markjhicks It's no secret, I've been posting updates on Facebook and Twitter, just not specifics about it's content. This video is taking forever to get up and running however but I think it will be worth it in the end.

[CRISTIAN123JOSE]

i was wondering, if there is any way o test it without taking it out with a smokemahine , thanks and good video

[markjhicks]

@CRISTIAN123JOSE You can smoke it, but it will not show if the VSV is activating. You can activate it with a 9 volt battery without removing it. This is what usually happens when they fail.

Mark Hicks

Wells Manufacturing L.P.

[Standingwithfeast]

markjhicks, I appreciate the video. the vaccum guages is a good way to check the valves.

[markjhicks]

@Standingwithfeast Thank you for the kind words. Problem is you have to have two of them. That might be an issue for some shops. Testing the VSV activation with a battery will reveal most of the failures.

Mark Hicks

Wells Manufacturing L.P.

[dmorley100]

Was startin to wonder if you were still alive or not. Great video though.

[markjhicks]

@dmorley100 Yep still kicking. Problem is sleep keeps getting in the way of making more videos! Glad you liked it!