Why replace EVAP canister vent control valve when the canister goes bad?

[mora2818]

I posted this same question at the end of a thread on replacing the EVAP system but it seems there aren't many views:

 

I have a quick question, in researching the fact that I have granules in my EVAP lines and I need to replace the canister, I haven't found why I need to replace the EVAP canister vent control valve. Can someone tell me why this is also necessary to replace?

 

Thanks,

Kevin

[sewebster]

I posted this same question at the end of a thread on replacing the EVAP system but it seems there aren't many views:

 

I have a quick question, in researching the fact that I have granules in my EVAP lines and I need to replace the canister, I haven't found why I need to replace the EVAP canister vent control valve. Can someone tell me why this is also necessary to replace?

 

Thanks,

Kevin

 

Could get screwed up by the granules?

[DJ Dank]

I was plagued with EVAP issues for a while before I figured out it was my vent control valve that was stuck in an open position due to all the water crossings I did. Luckily there was no charcoal in the lines. A tiny bit of WD40 freed the valve and allowed it to open and close.

 

Now couldn't charcoal in the lines possibly be related to issues with the vent control valve? If it was stuck closed maybe?

[rgallant]

Hi I believe it clogs the valve, I am doing mine this weekend, got a complete unit off a wreck. So I can open the old valve and see what it up, my bet is the there is an idiot sensor in there that gets damaged by the charcoal.

[mora2818]

Hi I believe it clogs the valve, I am doing mine this weekend, got a complete unit off a wreck. So I can open the old valve and see what it up, my bet is the there is an idiot sensor in there that gets damaged by the charcoal.

 

I pulled one off a wrecked rig and for a week or so I was good without a CEL light. I haven't pulled the code so i am not sure if I still have some EVAP issues or not. I think my pathfinder is dying a slow death. Cracked windshield with a run 2 feet long...check. CEL light on and I don't really care...check. Terrible squeaky wheel/hub/bearing from something I can't figure out...check. But it still drives just fine.

 

-Kevin

[revolutionary198]

Along with the exploding charcoal canisters, a real common issue for the R50's (mine included) is the valve dying since it's in such an exposed location. If the valve is stuck open, it makes it impossible for the EVAP system to run a pressure check, so it throws a SES code (P0446, maybe some others too). The bolts holding the valve onto the canister are just screwed into plastic female threading, so it can be a pain in the ass to get the valve off (grinder, hacksaw, etc...). But, if you can get those bolts to give, just hook a 12V up to the valve and see if it closes, if not give it a hit of WD40 like Dank suggested and hope that fixes things, but otherwise gotta replace the whole assembly.