Do you drive in dusty conditions much? We do vent valve and canister jobs like clock work out here in Oklahoma. The EVAP system gets air from the valve thats located under the truck which sucks up dust and dirt. Typically if you have a P0446 you are going to need a canister too because 99% of the time there is dirt contamination in the canister as well. GM has a reroute kit which consists of a different style vent valve and then you take heater hose and run it along the frame and put the remote mount filter box somewhere up in the engine compartment where the air is somewhat cleaner.

 

What kind of symptoms are you guys getting with a bad evap system? Taking a longer time than normal to start? What about a miss at idle? Just trying to narrow down a problem. Thanks

 

i still havent fixed my truck. i am in need of the relocate kit and sensor. the p0446 has not had any driving or running issues. no miss idle or hard starts just an annoying check engine light.. but runs great.

 

If it's an 07 why not make the dealership fix it?

 

tell me how and i will? 07 classic 65,000 miles. 100,000 mile drivetrain warrenty. can they fix it 4 me?

 

hmmm, if it smog related you are still covered.... Might try giving them a call...

 

thanks i will call..

 

i called, 36,000 mile only. kinda sucks that when i need something from gm fixed everything else is covered except the part i need... lol..

 

My mom's truck has this code as well. She lives down a dirt road so maybe that has something to do with it. I just set the code to "no MIL" for now. Is this just a smog issue or can anything bad happen from the canister being contaminated?

 

It's just an evaporative emissions issue, won't cause runability problems. Worse case scenario is the vent tube gets clogged and you might have problems with the gas pump kicking off while trying to fuel, but that's highly unlikely.