im having this smae problem right now...i was getting crazy terrible gas milage an the computer said the mass air flow sensor was bad...so i replaced that..an my canister has been all screwed up for a long time now....every since ive been bagged..because the idiot who did my bags screwed it all up...but yea now it has a hole in it an im having to replace it...soo i duno ...hope you figure it out

 

My truck threw a code today a P0455 and the guy at AutoZone said it was a large leak in the EVAP system. The book said it could be a bad canister, a bad manifold gasket, or severl other little things like check valves. I was wondering if anyone has had this problem before, also if it is the canister where is it and what does it look like? I would like to do this myself instead of paying some mechanic a bunch of money for something that I'm going to guess is simple to fix.

Any help guys?

BTW my truck is a 2003 Blazer Xtreme with 37,000 miles on it.

most of the time it's a loose gas cap, seriously.

 

Guess what? It was the gas cap.

 

Guess what? It was the gas cap.

I work at a Nissan dealer, and we get 1-2 a day in here for that problem.

 

That's really stupid, why would it do that?

 

because no pressure builds up in the tank so the evap system cant purge if theres no pressure pushing the fumes into the canister