P0446, already replaced VSV, code still exit..

[justthinking]

1999 Toyota Camry 2.2L 145k miles

Got the dreadful P0446 code a while back..1st thing I did was replace the gas tank cap which did not help..
Today I replaced the VSV by charcoal canister w/ an aftermarket Dorman one and the code came back up about 20 miles of highway driving..
should I try replace the Dorman VSV with OEM VSV again or should I move to next step of diagnose?
While changing out the VSV, I checked all the hoses around charcoal canister and all appears to be in good condition...
Is my best bet to simply replace the entire charcoal canister unit or are there some other place I can look before taking the plunge?

[Jason.MZW20]

There's a TSB specifically for this issue and only for 1999 Avalons, Camrys, and Solaras.

http://www.camrystuff.com/manuals/Ge...neous/TSBs.pdf

Go to page 142. A vacuum control valve needs to be installed onto the canister. If you don't feel comfortable doing this, print out the TSB and take it to the dealer. It won't be free, however.

The valve is around $30-40 and comes with the necessary hoses.

[Jason.MZW20]

I've noticed this is a very common issue for the 1999s, so I'm bumping this for the benefit of others who have needlessly spent hundreds of dollars trying to fix this code.

[TOYOPARTSMAN]

There are actually two bulletins on this;
one calls for a VSV by the canister 90910-12271 MSRP $79.31 and the other one is for vacumm control valve with hoses 25852-20010 MSRP is $31.35. Now I know no one in this forum pays MSRP. I just put that out there so everyone knows. If you want the actual TSBs let me know and I can send them to you.

Originally Posted by justthinking

1999 Toyota Camry 2.2L 145k miles

Got the dreadful P0446 code a while back..1st thing I did was replace the gas tank cap which did not help..
Today I replaced the VSV by charcoal canister w/ an aftermarket Dorman one and the code came back up about 20 miles of highway driving..
should I try replace the Dorman VSV with OEM VSV again or should I move to next step of diagnose?
While changing out the VSV, I checked all the hoses around charcoal canister and all appears to be in good condition...
Is my best bet to simply replace the entire charcoal canister unit or are there some other place I can look before taking the plunge?

[Jason.MZW20]

Yeah the canister VSV will give you P0440, P0441, and P0446 though.

Page 161 in the link.

[TOYOPARTSMAN]

Sorry, I forgot to through my two cents in about the non OEM parts.
I always use OEM parts, especially for emissions stuff. I have seen brand new after market gas caps not seat correctly, and the valve, I am not even sure if its the correct one. Whenever they have a different part on a TSB it usually is for a redesign purpose to solve a particular complaint. Not sure if hte aftermarket valve got the new specs. Just something to think about.

Originally Posted by justthinking

1999 Toyota Camry 2.2L 145k miles

Got the dreadful P0446 code a while back..1st thing I did was replace the gas tank cap which did not help..
Today I replaced the VSV by charcoal canister w/ an aftermarket Dorman one and the code came back up about 20 miles of highway driving..
should I try replace the Dorman VSV with OEM VSV again or should I move to next step of diagnose?
While changing out the VSV, I checked all the hoses around charcoal canister and all appears to be in good condition...
Is my best bet to simply replace the entire charcoal canister unit or are there some other place I can look before taking the plunge?

[justthinking]

I tested the old VSV today and it appears to be good..I can hear click when I apply power and the valve seems to hold vacuum just fine..
Since it's not the VSV..where else could I look for problem other than replace the entire charcoal canister?
I also checked the TSB for the vacuum control valve and my car's vin is not listed..
I remember someone mentioned another valve by the air filter?

[TOYOPARTSMAN]

Well, I am not a tech, but we do stock the charcoal canister which leads me to believe that you may have bite the bullet and replace it. It is a fairly common problem. I also stock the valve by the air filter, I am not really sure if that applies to the P0446. Before you go and replace the canister, did you try an OEM gas cap? But based on the code, and just the commonality, I think you may be headed towards the canister. The new canister will also have the updated VSV on it, so you'll eliminate that TSB as a concern.

I am sorry if this didn't help, I know the canisters can be expensive, MSRP is $343.09. If you do need to go that route, I do offer TN members a 30% discount off MSRP and only charge actual shipping costs plus $1.00 - $2.00 for materials, etc(I do mean a dollar or two). Later today, I'll ask a tech about the valve by the air cleaner and see if is part of the P0446 or not.

Originally Posted by justthinking

I tested the old VSV today and it appears to be good..I can hear click when I apply power and the valve seems to hold vacuum just fine..
Since it's not the VSV..where else could I look for problem other than replace the entire charcoal canister?
I also checked the TSB for the vacuum control valve and my car's vin is not listed..
I remember someone mentioned another valve by the air filter?

[ansul101]

I have the same prob replaced the VSV by the char canister and still the code is still there

[Jason.MZW20]

A lot of the time P0446 is caused by either the actual charcoal canister failing (aside from the TSB) or the fill check valve cracking (1999-2001 only). There's a possibility of vent line blockage as well. I'm dealing with P0441 and P0446 right now in my 1MZ MR2. Seems on average, these canisters last about 10-15 years depending on conditions. For states with salted roads, expect even less lifespan, especially for the VSV. I've tried two used canisters with no luck, so yeah, sometimes you do have to bite the bullet and get a new canister.

I took apart one of the spare canisters I had (a MY2000 Camry one) and there's not much to it. There are two compartments in the canister, the fuel tank side and the canister side (air inlet/drain). They're both filled with charcoal pellets and have a couple of filters to keep that charcoal in place. The bottom is spring loaded to compress the charcoal in each compartment. After that, it's just the two vacuum/air control bulbs on the front. Sometimes those stick open or closed as they wear with age. Since they're not removable (I've tried), you have to replace the entire canister. Sucks.

So, if new VSVs don't fix it, you either have a fill check valve problem (1999-2001 Camrys, 1999+ Solaras) or a charcoal canister problem.

[justthinking]

where is the fill check valve? before proceed to replace the whole canister unit, I would want to make sure it's not something else..

[Jason.MZW20]

Originally Posted by justthinking

where is the fill check valve? before proceed to replace the whole canister unit, I would want to make sure it's not something else..

In the fuel tank. You have to drop the tank to replace it, so that's no fun either.

[andyman66]

anyone have success by adding the vacuum control valve with hoses part#25852-20010 in getting rid of p0446? I know replacing the cannister will fix it also but this is a much cheaper route. Any help? Thanx in advance.

Originally Posted by TOYOPARTSMAN

There are actually two bulletins on this;
one calls for a VSV by the canister 90910-12271 MSRP $79.31 and the other one is for vacumm control valve with hoses 25852-20010 MSRP is $31.35. Now I know no one in this forum pays MSRP. I just put that out there so everyone knows. If you want the actual TSBs let me know and I can send them to you.

[TOYOPARTSMAN]

What year is your car, there is a bulletin on this part, but it looks like it only applies to the 99 AValon, Camry, & Solara.

Originally Posted by andyman66

anyone have success by adding the vacuum control valve with hoses part#25852-20010 in getting rid of p0446? I know replacing the cannister will fix it also but this is a much cheaper route. Any help? Thanx in advance.