For those with the P0446 CEL code...

[Ranger X]

Well, as some of you may know, I have been battling with my check engine light ever since two days after I bought the car. (It's a 99 Camry V6.) I would have it scanned periodically, and it would consistently report a P0446 code, no matter how many times I reset it. Well, I finally spent the time to diagnose the problem today. Using a haynes manual, I did pretty much every test that I could to possible problem areas. I now believe that I have a failed charcoal canister. The reason? While doing the last two tests on it, it failed to hold any vacuum at all. So now it looks like I'm about to have to spend $275 on a new charcoal canister. At least, that's what I think. Now, here's what I want to know. Is it possible that the two solenoids on the canister are bad, and not the canister itself? Because if that's the case, then I could simply buy another set of used ones from a salvage yard. Surely that would be cheaper. However, then I'd run the risk of getting some that had failed as well, and I wouldn't know until I had them installed. I'm just not looking forward to paying $275 for a part that shouldn't be bad in the first place. What causes these things to go bad? I have read that it's from topping off when you get gas, but I never, ever do that. Then again, I've had the problem ever since I bought it, so it certainly could have been a previous owner. One other question, can I drive the car without the canister on? Everything that goes to it is disconnected. Yes, I know it will probably trip all kinds of CEL codes. But I'm moving in a week, and I can't afford to buy a new CC, nor can I afford to have it towed.

[automaton]

Judging from experience I've had (on two different Toyotas) with 0446 codes, if I were in your shoes I'd try changing the charcoal canister vacuum switching valve first (about $55 from a dealer or somewhat cheaper mailorder). The part in question is one of the two little vacuum/electrical parts mounted on the end of the canister. It will have 2, or possibly 3, vacuum lines and a single electrical connection with 2 contacts. Both the ones I've changed failed because of corrosion on the little piston inside, probably from road salt.

HTH; automaton

[zoni]

i'd try a whole new assembly from a junkyard. chances are, the replacement will work fine for you.

[Ranger X]

Originally Posted by automaton

Judging from experience I've had (on two different Toyotas) with 0446 codes, if I were in your shoes I'd try changing the charcoal canister vacuum switching valve first (about $55 from a dealer or somewhat cheaper mailorder). The part in question is one of the two little vacuum/electrical parts mounted on the end of the canister. It will have 2, or possibly 3, vacuum lines and a single electrical connection with 2 contacts. Both the ones I've changed failed because of corrosion on the little piston inside, probably from road salt.

HTH; automaton

I tested the VSV for the EVAP and the VSV for the vapor pressure sensor, and both were fine. However, I didn't test the vapor pressure sensor itself, so that could still be a problem. Either way, I am still pretty sure that the CC itself failed.

[FrankXT86]

Same thing happened to me, 2 days after I got my camry, BAM...CEL.

Took it to a local mechanic, found out it was a twisted vacuum line, all I had to do was pay for labor.