Curious if I could get some advice/info on what may be causing this problem. I have had this code for some time now. It originally only popped up when I was constantly in stop and go traffic after like a day or two, but would never pop up when I would drive long distances (drove from Detroit to KCK like 3 times and never popped up during those trips). I would clear the codes and it wouldn't pop up for some time. That was until recently, I am doing some stuff to my 4runners in regards to cleaning the rust off and coating it and dropped the spare tire, that's another story, but ever since I have done that the code has popped up every 60-100 miles no matter what with P0446 being the first confirmed code with the others being pending. Im certain that it doesn't have to do with the gas cap and fuel filler neck. I personally am leaning towards the charcoal canister assembly and or one of the hoses attached to it with a hole in one of the hoses that may have gotten larger. Any thoughts or ideas? Thanks

Not to be vague, but it could be any number of items tied to the emissions/evap system on 2001/2002.

There are some quicker fixes (new OEM gas cap for example) but if your system has rust it's possible it also has old hoses, any one of which can leak, breaking the seal on the closed environment. There is also a gasket on top of the gas tank that supposedly fails.

I have a 2002 SR5 4WD that I purchased in 2021. It also had these codes. I chose to replace all hoses, relays, sensors, gaskets, charcoal canister, pipes, etc. with new OEM where possible. Mine was old enough and crusty enough to not try to chase it with point fixes. There is a good thread on this here on the board. I just got it on the road last week and so don't have a final answer on if I "fixed it".

Wish I could be more actionable. Perhaps since you poked around near the charcoal canister (spare tire), look there to see if something wiggled loose. It may be a simple matter of plugging a hose,pipe,electrical junction back in.

Your goals for the vehicle will dictate the direction to take. If it's a forever truck, then do what you gotta do. I think there is a thread or two on manually forcing the VSC/Trac system on/off, or bypassing the emissions system entirely. Not sure but I think I've seen it.

~Jason