Evap codes (ALL OF THEM). Where to start?

[sibanez]

My ex-wife bought a 4Runner to use at her cabin on Friday and the car threw several EVAP codes on Monday.

Codes include:

P0446
P0441
P0442

We checked the gas cap and that appears to be sealed shut. The car does have a breather for the gas tank that runs to the fill spout . . . before we go crazy, I'd like some advice. Reading through the archives, I already checked various hoses connected to the canister and all seemed well.

 

[BlackWorksInc]

I'd say it's probably the canister itself, most likely the Vent Solenoid has failed (I've seen this on some other Toyotas in our area) which is unfortunately part of the canister assembly.

Have you thought about taking it to a shop to have it double checked?

There's some circuit checks and vacuum checks you can do; but honestly it's a much easier thing to do if you have a scantool that can bi-directionally command the solenoids to activate and close while you're testing the system.

 

[jimbohotwings]

I had the same amount of codes and it was the gas cap. it wasn't sealing properly. i think it was 30 bucks at the dealership.

 

[gmhotch]

Just replace the gas cap first and see. I had the same exact codes and I picked up a new gas cap for $14 bucks. Clear the codes and test drive it, you should be good to go unless the canister really failed.

 

[BlackWorksInc]

Gas Cap is not something I would typically associate with a P0446, but it's not out of the realm of possibility.

There's an old TSB for this condition that may be worth looking into, it suggests a possible failure of the purge solenoid (your vehicle is a 2003 right?).

View attachment T-EG020-03.pdf

 

[sibanez]

Thanks, I will look into this. I did notice that the nipple in the gas tank that runs to the vent by the fuel cap is loose on the tank side . . .looks like it may have been broken off. I'm guessing that's causing at least one of the codes. Going to try some putty poxy to seal it up.

Gas Cap is not something I would typically associate with a P0446, but it's not out of the realm of possibility.

There's an old TSB for this condition that may be worth looking into, it suggests a possible failure of the purge solenoid (your vehicle is a 2003 right?).

View attachment 218716

 

[clh333]

Evap can and codes

My 2007 4Runner Sport began throwing the same codes, at first occasionally and in colder weather, then all the time, from 2014 to this year. Dealer diagnosis was to replace the cap ($70); didn't help.

I live in a state that requires passing an emissions test, so ignoring the problem was not an option. Dealers wanted $1200 to $1500 to replace the can, so I dragged my feet until I found a mechanic who performed a vapor test and fixed the problem by "unsticking" the solenoids in the evap canister. "Happens all the time", he said.

The canister is fairly easy to access from underneath the rear of the vehicle if you remove the spare first, and pretty straightforward to disconnect. Makes me wonder how the dealer justifies the price charged for replacement.

 

[jbd]

I recently had these codes come up but after cleaning the o-ring on the gas cap I have not had any problems since.