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1999 Camry charcoal canister and control valve

I’m not terribly auto-savvy, so any help I could get here would be great. My 1999 Camry has 109k miles and the engine light came on a few days ago. Took it to a shop, and he told me it turned up as code-p0446, if I remember correctly. He said I need to get the charcoal canister and control valve replaced, and the bill (parts, labor and scan included) will run me just over $550. Is this a reasonable price for the fix or should I try another mechanic? Or is this an easy repair that I could do myself if I buy the parts cheaper (and have no car repair experience whatsoever…)?


About 100 years ago, in answer to a question about how much his huge yacht cost, Commodore Vanderbilt replied, “If you have to ask, you can’t afford one”. In a similar vein, when someone with “no car repair experience whatsoever” asks if he can do this repair himself, I respond that, “If you have to ask, then you can’t do it yourself”. To be blunt, your attempt to save money has the potential to cost far more in the long run if you make a mistake. And, since this system deals with explosive gasoline vapor, the potential cost involves a lot more than mere dollars.

That being said, the price sounds a little bit on the high side, IMHO. You might be able to find a mechanic who would do this job for…maybe $75.00 less than this guy’s quote.

Did they check filler tube, check valvue and vent hose from filler neck to canister?
Any of these that are clogged or bent will cause engine light.
Be careful with places that want to replace parts without checking, they are called parts changers and they keep replaceing till proublem is fixed.

VDC, I kind of figured that was the case, but I was hoping it might be easy. And the fact that a dealer told me the bill sounded “about right,” probably means it’s a bit on the steep end.

As for what they checked…I didn’t think to ask, and the invoice doesn’t mention that. The interesting thing about this is that this is a car I bought from my dad, and in the summer of '06, he took the car in with error codes PO443 and PO446. They replaced the “evaporation control canister” and that seemed to fix the problem (pressure vsv not opening and closing, failed canister assembly). Is that canister the same as the charcoal canister, and if so, shouldn’t it last as long as the car is on the road?

Are there a couple quick checks I could do to see if maybe it’s just a valve issue? Or is there a way to reset the monitors myself so I can see if it’s just a matter of the gas cap needing a good tightening?

I don’t know what the set up is like on a Camry, but if you are interested in getting more involved in your own car repairs I can think of worse things to start on. What you want is a repair manual - most any auto parts store (especially the large chains) carry the Haynes line which are fine. One of these will run you only $20 and if you plan to try to keep the car going for a while I’d argue that its a worthwhile purchase even if you never fix anything yourself. Information alone is often worth its weight. (You’ll probably make back your $20 the first time you need to replace a couple of bulbs).

You can also easily price the parts online and at least find out what your approximate parts cost would be. For the charcoal canister you might check salvage yards instead of new parts. Then if you buy a manual you can check out the procedure and decide whether or not you’re up to it.

Do you know how the mechanic arrived at the canister and valve? What were your symptoms? Evap system codes seem to produce an awful lot of repairs with recurring codes due to guessing. (e.g. pay attn to the post from hd72mm) If I were you I’d start by carefully checking all of the vacuum lines in the evap system and replace the valve first - unless the canister reeks of gasoline.

And stop topping off your gas tank. Just fill it until it clicks off the first time and then leave it alone.

Unless you must pass an emissions test, this can wait…For $550, it could wait a long time. It’s probably just a split vacuum hose near a fitting. The world will not end…

I will call him and ask how he came to the conclusion he did.

I’ve never actually topped off the tank, though this time I may not have turned the gas cap all the way to the audible click.

Thanks, if I get the time I’ll look into the repair manual, but I’m probably better off starting with a smaller job. Maybe the valves, but maybe I’ll just find somebody I can help build a car, to become more familiar with it.

The code P0446 is, “Evaporative emissions system vent control circuit [has a problem]”. It doesn’t say to change anything. Last summer, parts were changed. It’s unlikely that those new parts fixed anything. What is more likely is that they did something else which “fixed” the problem for a while. It sounds like this latest place has only scanned the code and jumped to the plan to change some expensive parts, again.
On this site: scroll down and read Qslim’s response. Ignore the others. Check all the vacuum hoses on, and about, to, and from, the charcoal canister, for cracks, splits, and deterioration, and connection.

Well, things just got more fun, as the engine light went off this morning. It was warmer with a heavy fog, though I don’t know if or why that would have anything to do with it. Does this suggest a problem other than what the mechanic indicated, or no problem at all?

I have the same 1999 camry. Here’s a recent history (engine light comes on):
1/24/2007 Goodyear Auto–replaced Evaporator canister and control valve $549.19
7/12/2007 Goodyear Auto–replaced Purge Solenoid valve $134.24

11/8/2008 Toyota Dealership–Replaced Charcoal canister and Purge Valve (Toyota says they still have to charge this) $656.75
2/9/09 Toyota Dealership–Estimate today for Replacing Vacuum control valve–for $135.00
I have not authorized the work yet.

I know people are rolling their eyes at the work I had done to this car. I asked friends (who do their own auto work) and I try to educate myself. I really don’t know what to do. The Camry has 89k miles; I still love the car. But the cost of repairs is starting exceed what I think the car is worth. Any ideas? Advice? Suggestions? Thank you, everybody.

Ideas, suggestions, advice have been given. Would you like an ironclad guaranty on that? Links were included for a reason. Check them out.

The reason you got this problem in the first place is that you regularly overfill your gas tank. When you fill the tank beyond the first click of the pump handle, you reduce the headroom in the gas tank for expansion of the gas.

FYI, I had this happen to me, even though I knew not to overfill, but I though rounding up to the next dollar would be OK, but it wasn’t.

The gas enters the tank at ground temperature and will expand if the air temp is higher. If the headspace is not great enough, excess vapors and even raw gas gets pushed into the canister. At some point, right after filling the gas tank, the canister got saturated and tripped the light.

After a couple of days, the canister dried out enough to let the light go out. If you stop overfilling the gas tank, stop on the first click, you should not see this code again.

Anytime something like this happens you need to ask shop why part failed, millions of these parts last 200,000 mi.
What other things could cause code and how were they checked. If you do not find cause it may fail again if indeed it is canister.

From Keith’s comment about overfilling the tank, I never do that. So that’s definitely ruled out. I should note that before I went to the Toyota dealer, I took it back to Goodyear. Goodyear and Toyota both concluded (independently) it was the charcoal canister. I asked the service manager at Toyota, he said the charcoal canister design has been updated in the last year and I shouldn’t experience the problem again.
Hd72mm, thank you the for the “why” and “how” questions. I will ask more questions on Wednesday. I looked online, and the Toyota Camry in these model years had similar problems. Thanks for everyone’s help.

This thing seems rampant, throughout the auto repair industry, (thus the “agreement in (non)diagnosis”) to use the trouble codes, alone, as an excuse to avoid doing any actual testing, checking, troubleshooting, and to CLAIM troubleshooting actions were taken, or there are “other” justifications—such as a “new and improved part” has been released. If so many of the former parts were deficient, the car makers would be forced to recall those defective parts. In short, I don’t think that the appropriate checks have been made, still.
I doubt both types of places which have given their (unsubstantiated?) opinion.

My 2002 Sienna had a similar problem, though intermittent. I did a lot of research, including online and shop manual, and concluded it was the canister. But, mine would only happen like once a week, sometimes less. A man on Sienna club had the same intermitten, but had two Siennas. He swapped canisters between them and it followed, so I took a chance and had it replaced. I told them I had troubleshot it already and did not want someone to try to find something that is not going to fail in the shop anyway.

However, before you pay the money, since it went off again, be very careful to click that cap each time. Also, since they only cost around $20 buy an official gas cap from the Toyota dealer. Others have reported generic gas caps have failed a lot. Then, if it still fails, you will probably have to try it.

interesting, autozone told me I had P0446. gas cap is tight, I cleaned it to make sure no dirt, rust or other things were keeping it from sealing. I put the car on jacks and got on my creeper and checked the hoses, nothing pinched, wires tight and I don’t see any cuts on them. I checked the air cleaner and all looks fine there as well. It was quite warm yesterday and I noticed when I took the gas cap off there was a lot of bubbling noise coming from the tank (7/8 full). I will hold off a couple days to see if the light goes away. I did pull the EFI fuse in hopes of resetting but that did not work either. BTW, I have an 03 Camry XLE 6 cyl with 102K.