[QUOTE=JFP in PA;6678513]The canister itself is a passive device; what cause the codes and other issues are either failed valves that control the vapor flow to and from the canister, or blocked lines that prevent the vapor flow, or lines that become disconnected and cause vacuum leaks into the intake system.
The canister is a charcoal filled chamber that absorbs and stores fuel vapor from the tank and then vents it into the intake system to be burned when appropriate. All the rest of the hardware just moves the vapors around.
QUOTE]
So JFP. When it gives us the code.
P0446:
Shutoff valve activated charcoal filter (function) below limit value
Does that mean that the vapor has turned to a liquid or the charcoal filter is clogged to the point it won't operate correctly? I think that is what you mean. Like an air filter that gets clogged full of dirt. Just checking and it may help others on here to understand what it does. Not trying to over think things. Or bug you. But I love knowledge of how things operate and why.
I tend to research the crap out of everything. Well except my first wife.
Hope all is well in PA.
Randy
Randy