Itsmeagain

02’ ES300. Throwing P0441 and P0446 (still pending as CEL was reset recently after solved P0420/P0430 and P0128).

Are there common problem areas for these two EVAP codes? Car has 256k miles on the clock. Gas cap looks to be in good condition. No suction at purge valve behind air box. Charcoal canister has probably never been replaced (bought the car with 95k miles and haven’t replaced it).

Im on a quest to keep this thing going and to do that I need to pass state emissions testing. Otherwise, the tags will expire and it won’t matter how good she runs lol.

Thanks in advance!

HomerJay

Although it may visually appear to be OK, replace the fuel cap with an OEM equivalent. Gas caps wear out and are unable to provide a tight seal, also make sure the fuel neck is clean.

das1960

FWIW, gas cap is basic starting point. If you have the original, replace the gasket it is $6. On mine, I recently found a small spilt at the far end of the line running from the green test port at the back of the engine compartment to the little valve assembly on the intake manifold.

Itsmeagain

That is too funny, I just replaced this hose last night after finding it cracked and petrified so I’m pretty sure that’s gonna be it!

The little plastic air box that that hose feeds into also snapped into 3 pieces while checking the canister purge valve, but I just bypassed that guy. We’ll see how necessary it was after my commute lol.

I was really kinda shocked at how brittle everything in that area is (possible due to the beauty cover trapping heat, it’s been removed for good). Going to try to find a full vacuum line replacement kit.

Will update later with code situation later!

FromFL

Taking things here off track a bit, how'd you solve the P0420/P0430 codes? I'm fighting those, hoping beyond hope I don't need new cats but I know better.

Itsmeagain

2 spark plug defaulters from Autozone, drilled out with 1/2” drill bit to accept the downstream O2 sensors so they aren’t directly in the exhaust stream. Not a “fix” necessarily, but if I my cats are operating at 93% efficiency instead of 95% I don’t think I’ll hurt the Ozone too bad lol.
I’m sure you know the cats are one with the exhaust manifolds, and spending $2500+ on a 20 yr old car just doesn’t seem logical lol.

Also it doesn’t hurt to check your air filter, clean the MAF sensor, and PVC valve as I’ve heard these can cause the codes. I did have a bad PVC but that wasn’t the overall issue it was the cats.

Good luck!