P0449 Code

[Tractordoll]

So my check engine light came on today and it was throwing code P0449. From what I can see it is one of 2 possible causes. But I also wanted to see if it is possibly a leaky gas cap. The gas cap on the truck is the original since new and never replaced. So today I replaced the cap and reset the code to see if that fixes it. If I get the code again, does anyone know the correct GM part numbers for the gas cap vent solenoid or the purge solenoid? Thanks in advance to anyone who can help. This is on my '05 H2.

 

[Big2dabank]

I think I threw that same code a couple of years ago and it was the evap canister and not the gas cap. I took off the evap canister and cleaned it as best as I could and the code has never come back. Evap canister is located on the drivers side of the truck, outside the frame rail about midway.

 

[Tractordoll]

I think I threw that same code a couple of years ago and it was the evap canister and not the gas cap. I took off the evap canister and cleaned it as best as I could and the code has never come back. Evap canister is located on the drivers side of the truck, outside the frame rail about midway.

Does removing the evap canister require removing the rock rail?? It's been a while since I have looked at that part. The last time was when I went over the undercarriage of the truck and repainted.

 

[Big2dabank]

I removed my rock rail, because it was easier to get to the canister.
I got the code about two weeks after this water crossing when I was filling up with fuel, the evap canister started to leak a ton of water out of it. Once I removed it an cleaned it out as much as could, the code went away and has never returned.