P0446/P0440/P0441

Thanks to corolla2001 and drrmorgan. Info on the vacuum switching valve was right on and replacing it seems to have solved my CEL issues. Found an online source for the valve. It's called Toyota Parts Cheap. http://www.toyotapartscheap.com
It's the online storefront for a Toyota parts department located in CA. (They only sell OEM parts.) As it turned out, the part was discounted just enough that with the added shipping, it worked out to the retail price (about $75). But they shipped it to my door and I didn't have to fight with my local dealership's parts department. I used the part number that drrmorgan posted (9091012267). When I inquired about it to the parts supplier, they said that Toyota had recently changed the numbers in their inventory system and that had created some confusion. Not sure exactly what the story is with that, but if you're trying to get the part from a local parts department, it would probably help to give them the number rather than have them search my year, make and model. Thanks again for the help guys!

I've been getting a 441 and a 446 code on my 2001 Solara with a 4 cylinder. I don't remember ever getting a 440 code.

I tried merely changing the gas cap but I did not buy a Toyota cap unfortunately, I do not have a Toyota dealer close to me so I don't go there unless I believe it to be a critical part. Sounds like I need to rethink that.

At any rate, I've read through these posts several times and I think I have most of it understood and it seems that most agree that a bad gas cap won't set a 446 code anyway. I have tested the VSV for EVAP and it seems to be fine, it holds a good vacuum until I apply voltage to it, then it opens and passes air just fine. I did not see the VSV for CCV unfortunately ( and it is right next to the EVAP valve, too!) until after I had gone through all of the testing on the canister. I checked the VSV for Vapor Pressure Sensor and checked the Vapor Pressure Sensor itself according to the Haynes manual and all seemed well. I did have some trouble with testing the other two valves on the canister itself, which I don't know the names for but one is where the air inlet comes from the air cleaner, controlled by the VSV for CCV, and the other is hooked to the EVAP port, which goes to the tank itself.

They seemed to do what the manual described except for one obscurely worded test in which you apply 1.01 in-Hg vacuum to the purge port and cover and uncover the air inlet port watching all the while to see if the vacuum decreases at any point.

Tonight after reviewing all of this I saw that there is another one, the VSV for CCV, or Canister Closed Valve. When I apply a vacuum to the valve with my hand pump in its normally closed state, it bleeds off quite rapidly initially but slows down as the vacuum decreases. That would seem to indicate that it is bad to me since it won't hold a vacuum. I put a small amount of silicone grease on all of the vacuum lines and rechecked it just to be sure I did not have any leaks and I got exactly the same result.

Does anyone know if this is normal operation for this valve? My Haynes manual does not provide a test for this valve which is how I missed it until I read this forum and went over everything with a fine-toothed comb tonight.

I am puzzled by a statement in the Haynes manual that says that at times there will be pressure in the canister but when the engine is running wouldn't there always be a vacuum? I would like like to have a description of the theory of operation.

Thanks, Gary

pressure from the tank because of expansion, vacuum from the engine. I think you're on the right track. Haynes manuals are kinda vague. Being how big Toyota were in sales I'd figured there was one in just about every town.

Gary - The way I found the bad VSV on the cannister was to apply voltage and notice that
there was NOT a loud click, which indicated to me that the valve was stuck. (When I tested
the ones under the hood I could clearly hear the click.) Being under the car in the rear,
that cannister VSV gets a lot ot weathering which is probably why it goes bad.

Jeff,

You are right about Haynes manuals being a bit vague. I bought the factory service manual for my daughter's Hyundai and it is just great because 1) it is very specific and 2) for the vast majority of tests it gives instructions for using common tools. I have not tried to get the FSM for our 2001 Solara because the excerpts that I have seen on the internet have often called for vehicle specific tools such as scan tools with bi-directional communication which I believe you mentioned having access to.

There are Toyota dealerships in surrounding towns but it is kind of a long drive given the amount of traffic in and around Houston, not in terms of distance per se but in terms of time. I usually wait until the weekend and make a Saturday run to one particular dealership that I like.

Hopefully, the VSV for CCV will fix it. I feel that it should hold vacuum and it is not so I will replace it first before I go to the expense of switching the canister. Thankfully that VSV is really easy to change, not like the canister. I am going to buy it and a new gas cap from Toyota. I will change one thing at a time so that I know what actually fixes it. It just bugs the heck out of me when guys changes several things all at once because then no one really knows what the problem was. The seal on the old factory gas cap is dry and cracked, that is why I changed it initially. I used a Stant cap but I would feel better at this point with a Toyota cap.

BTW, our previous Camry was a 1990 and I tried to buy a factory service manual for it but was unable to. Do you know if Toyota sells a factory service manual to the public for these models and will it be helpful to me? I have a pretty good supply of tools such as digital VOMs, vacuum gages, hand vacuum pumps, and I have an Actron scan tool, not just a code reader but a scan tool for live data but if most of the procedures are written for Toyota's own scan tool it won't do me much good.

Thanks,
Gary

Seems to me I remember the vsv being the known pattern failure on alot of toyotas according to the website D-tips. It's a good site but you need to be a member now to see everything. I think You're right in your assumptions. Something to do with the cannister charcoal breaking down and causing the valves to stick seems to ring a bell. As for the manual being available if anyone can order it the dealer parts dept might otherwise Alldata is excellent.

Jeff,

What type of scan tool are you using?

Gary

I just put a new VSV for CCV on the 2001 Solara, the Toyota PN is 90910-12199 and it cost 57.34 before tax. I cleared the pending codes and will check in a couple of days to see if they reappear. I expect that it is fixed however because I tested the new solenoid and it operates as I thought it would, which confirms that the old one was in fact bad since it would not hold vacuum while energized and the new one does. BTW, this VSV is physically next to the VSV for EVAP, which is at the head of the system while the VSV for CCV is at the end of the system and is installed on the side of the air cleaner. It is not under the car, neither is the EVAP VSV.

Interestingly, my son's 2001 Saturn's MIL came on on the way back from the parts run to Toyota. I have been working on the Secondary Air Injection System for a while now, it is what us old-timers call the smog pump except now they are electric and controlled by the PCM. The original pump's bearings went bad so I replaced it with a used pump for $20 from a local salvage yard, a new pump is over $220 from Saturn and is a dealer only item. When the MIL came on again after 3 months I replaced the pump a second time with another used pump, again for $20 and decided that if this did not fix it I would bite the bullet and get a new pump next time. However, I think I jumped the gun because I noticed that there is water in the pump now when the MIL comes on but the motor runs fine and has a nice strong flow of air (after if blows about 8 ounces of water out). Since I had been on this tack of working on VSVs for the Solara, my eye was drawn to a VSV that opens and closes a valve that allows the pump to inject air into the exhaust. I tested it and it is in fact bad. I surmised that since this is stuck open and it is allowing moisture and exhaust gas to flow into the pump that is what ruined the first one. To my shame I didn't even test the second pump, when the same code came up and I saw that it was full of water I incorrectly assumed that it had gotten full of water at the salvage yard, I am not at all certain that it was in fact bad. So I will now change the VSV and see it that cures the MIL.

All that to say it is so nice to be able to apply what I learn to other situations and it is a good reminder to analyze, analyze, analyze, throwing parts at a broken vehicle is, in my opinion, and as the Brits say, "bad form!".

Cheerio!,
Gary

The chrysler suppplied DRB3 it's called!

It's back!! After several hundred miles, the code returned. I tried re-installing the old factory gas cap. I checked to see if I get that "giant sucking sound" (anyone ever hear Ross Perot's famous NAFTA speech?) after the car sits a while after being driven and I do. I don't recall if I checked that on the replacement cap. I did not know to let it sit for a good long while before removing the cap to create a vacuum while it was still on there. I cleared the codes because evidently the system will not operate while it has the Evap code present. Once I cleared the codes, the Evap VSV began cycling properly again. I did some other tests by manually activating the solenoids and I am able to get a nice flow of air through the canister with the Pressure Switching VSV off and the Evap and CCV VSVs on and I get a good vacuum on the canister if I close the air vent tube with my thumb. I get a good vacuum on the fuel tank when I activate the Pressure Switching VSV with the other two still active.

Now however, when I test the CCV VSV, it seems to be leaking like the old one was but not quite as bad. I am tempted to go back to Toyota and ask to for a replacement VSV, I am glad that I had the foresight to check the new one to see how it operated before I installed it. The CCV VSV is installed in the air cleaner box so there is no chance of it being clogged with charcoal particles. Air flows into the system via the CCV to the canister. The Pressure Switching VSV leaks slightly too, I just don't know how much of a leak would be acceptable and it is entirely possible that it could have charcoal particulate in it. The Evap VSV does not leak at all as long as I test it in the direction that it is designed to prevent flow, which is toward the engine. Right now I don't know what to try other than I did discover that Toyota's FSM for the 2001 Evap system should have been updated because my system is the later type of Evap system that is called the intrusive type.

Any help would be appreciated,
Gary

sorry to hear that man. check the new valve and the remainders and see if there isn't charcoal particles from the cannister sticking your new valves. I know you're jumping power to the valves and getting them to click but is there a chance you have some excessive resistance somehwere in the circuit that is preventing the solenoids and valves from working properly all the time. The other post on here lately talks about a harness going bad to the valves on the sunfires and cavaliers. maybe you're experiencing something similar?

This is where I wish that I had a scan tool that is able to communicate both ways. I would love to force these VSVs open via the PCM with the scan tool so that I am seeing things from the PCM's point of view because you're exactly right in that I can jump power to them and test the coil but that tells me nothing about the wiring harness nor do I know if there is a burnt out relay in the PCM that operates the solenoid. I can only say for sure that the VSV for Evap is cycling, I can hear it and feel it and I can pull the vacuum line off and feel and hear vacuum. As far as the others go I can't find a good enough theory of operation on the system to tell me when to watch for the other two to operate. I would like to fix this myself so that I can understand the system; this is a hobby to me but if we get close to inspection time I may have to give up and take it to Toyota. Hopefully, if it comes to that, they will be accomodating enought to satisfy my curiosity and let me in on what the problem is. Until then, for my own education, I will continue to try this.

I am considering upgrading my scan tool to the Actron 9190, which was not available I don't believe when I bought my 9145. I am not sure that the 9190 even has bi-directional communication, though. I really wanted one of KAL's models (I don't have the model number here at work) that did have bi-directional but SPX bought them and OTC and is shutting KAL down because SPX feels they are a direct competitor; so there will be no further support. I think that is a crying shame becasue I believe that KAL was a superior line.

The KAL was a bit less than $700, which is a little pricey for me but I was still ready to do it until I called them and found out about the impending demise of the company.

Do you have any suggestions for a bi-directional scan tool that would be around that price range Jeff?

Not that I know of for that price range. Maybe a used snap on mt2500 updated and equipped with toyota software. Hard to recoup that investtment though versus having a good shop or the dealer do it.

I've been working on cars since I was 12 so that is 35 years; a couple times along the way I have gotten tired of it and considered giving it up but I really do enjoy it the majority of the time and I have almost always been successful at fixing whatever was wrong. All that to say I have gotten a lot of use out of my current scan tool; it has paid for itself many times over in just two years and unless I get injured or something I will get a lot of use out of the next one too. Having said that I still can't spend more than about $500 right now so I probably will be sticking with what I have for the near future.

Thanks, Jeff.
Gary

by no means Gary am i saying stop but bi-directional is what costs money and for this instance it may be hard to recoup the investtment on this paticular instance when you're present setup is working so well