My SES light came on a month ago. I went to autozone and it came back with code P0455 (evap large leak). So I replaced my gas cap with a new one, reset the light, and crossed my fingers. Yesterday the SES light came on again. Now I have two codes P0455 and P1448 (EVAP canister valve open).

Anyone have any advice? Replace the whole EVAP canister? It seems like it's just hoses and easy to replace, but i think the part is a couple hundred.

 

Check the hoses on it one of them might have a leak then just replace it

 

canister could be cracked, I've seen that a few times, or the valve is stuck open. If it's the valve you can buy it separately but it sometimes cracks the plastic canister when it is removed and then you will need to replace that too.

 

I brought my car to the mechanic - he tested the evap canister, the valve, and gas cap. The canister and the valve came back fine, but when he pressure tested the new aftermarket gas cap, it came back with leaks. He said that his repair software has a big note that aftermarket gas caps should not be used because there have compatibility issues. So it seems like my original gas cap went bad and the aftermarket one was just bad from the start.

 

if u brought it to the mechanic and it's still there, ask him to smoke test the system and look for the leak
voila!

 

I threw this same code, I found that I had a crack on my canister, I just put some epoxy over the crack and the code eventually went away. I think those canisters can be kind of expensive.

 

A side note on this issue for anyone else getting this code:

for what its worth, the EVAP system is all just meeting govt. regulations anyhow. It simply recirculates air from the gas tank into your intake instead of venting it to air.

In my 97 I vented the hose coming from the gas tank to air and capped off the EVAP valve it plugs into so i didn't lose any vacuum. Then i just lived with the engine light. No harm done, just not as emissions friendly. Should you be on a tight budget, that can get you through till you can afford to replace parts. It beats leaving a clogged valve putting pressure on the gas tank.

 

160 something plus taxes!!!! damn, i might have to change mine, but where did you find the crack?

 

i have the same code, and plus p1448 pending, p1800 and p1800 pending.
what does "pending" mean?

i replaced the gas cap. and reset the computer (unplugged the negative batt. cable), reconnected the cable and the SES light came back on in less than 2 seconds!!!

 

Resetting the ecu and clearing a code are not the same thing. If the problem was really due to a bad gas cap and the new gas cap is good, the code will clear itself after a while.

 

I have been driving with both of those codes for a few months now. My mechanic said the valve is just stuck open, and there is no need to get this fixed. The problem is if other codes come up, I won't know, because the SES light is on anyway.

It looks easily accessible, so it looks like an easy job if replacing both. I wonder if I could find the canister and the valve used somewhere, although don't know if it's something junk yards would sell.