35k miles and check engine light???

My truck now has 35k miles and for the last few thousand miles my truck has intermittently thrown the p0441 code for improper purge valve flow or something like that. I clear the code and it will go away for a while (weeks at a time) and then come back at random.

The only thing I have noticed is it seems to happen when it's cold outside (below 10ish degrees) and rapidly warms up during the day to above freezing. Any ideas? Is this just a quirk of the tundra? The thing that bothers me is that it just started this year and didn't do this last year.

 

Try replacing the fuel cap...

 

^^

 

Looks like you are still under warranty, I say take it to your dealer and then it is documented that there is an issue.
Not trying to be a butt head.

 

Not sure which truck you have as there’s nothing in your profile there. As previously mentioned, fuel cap. Secondly, if you’re filling your truck up, then squeezing another couple squirts of gas in to “top it off real good”, you’re damaging the fuel vapor containment system in the truck. Fuel is backing up into the valve that is supposed to contain the fuel vapors (EPA stuff) and ruining the part.

 

Question about this.... Suppose you only fill the tank to 90% and head up or down a steep grade directly afterwards. Would that not cause the fuel neck to become completely full? Maybe the check valve would prevent it. What do you think?

 

I can’t imagine any amount of normal driving will cause this failure. A rollover? Maybe.

 

So do you know if there is a check valve at the base of the filler neck to prevent backflow from occurring?

 

There is an anti-siphon valve to keep someone from pushing a tube down the fill neck and swiping your petrol.

 

Is that device more like a grate of sorts, perhaps like a "x" or maybe an "x/o" combined that simply form a barricade and not really a valve? I still think if the tank was say 90% full and tilted at a 50 degree angle then the fuel neck would become completely full unless there is a check valve to prevent the fuel from backflowing up the neck.

 

just posting this for anyone that may come across this in the future. I ended up going to my toyota dealership (hate those places) and they tried to charge me $200 diagnostic fee, plus $220 for the purge valve solenoid, plus labor! I had to stand my ground and may have said a few choice words. In the end, they let me drive my truck away without paying for anything.... though they did not give me the part. I ended up ordering it from sparks toyota for $75. It's a simple 5 minute job... if that. Not sure why mine was bad, but apparently it was. Since replacing it, the issue has resolved itself and gone away.