Hello Yotatech members. I have a 245k 4Runner I4 2.4L. It has 245k on it, and it has a check engine light with code P0446 showing. I've swapped the gas cap and reset it. The vehicle hesitates when driving, especially on the freeway, and it has little power for this small 2.4 L 4cylinder.
I read somewhere about replacing the vacuum-switching valve to see if it makes a difference. Or should my next replacement part be something else like the charcoal canister or something else?
The filler neck doesn't seem to not want to take the fuel. So I don't think there is an issue at the tank level.
Should I pull one of the plugs to see what they look like as well?
Maybe replace the plugs and coils?

 

Well welcome to all the fun! Boy have I been here!! OK, so. . . This is the order of operations I followed before throwing all the parts at it. . .which in most cases is what is required to fix this little problem. 1. Check all the vacuum lines and replace anything that is just suspicious. With those miles, just replace the right off. That is everything from the air intake to the egr to charcoal canister. Clear the code give it a run time. If it comes back, go to the next. 2. Change the Vent Solenoid and the purge solenoid, yep both. Once you replace one, the other goes bad. They are pretty sensitive. Clear code, drive. If again comes on, 3. Change charcoal canister. 4. change the tank pressure sensor. Don't cheap out here, get the rubber grommet and the hard line. Mine had a dried out seal and pin hole in the hard line. . .and I live in Georgia! When you drop the tank, just replace ALL the rubber, trust me our trucks are aging. 5. just get it all done and don't waste time thinking about saving a buck. Our trucks love to just run up the bill at these miles.
Get only Toyota parts. Go on the web and find the discount dealers. These are real dealers that sell at great discount. here's a link: parts@ToyotaPartsOverstock.com
Good luck!!