02 D2 se7 with 163,665 miles

I have had this p0442 code for a while now. I just built a homemade evap smoke tester and used it today. I found smoke coming out from this square shaped canister that is behind the coolant overflow and it has a 2 wire plug and a fairly large hard plastic hose on one side. My question(s) is what is it called and is it supposed to be leaking smoke/vapor? Do I need to block the flow for smoke test?
initial smoke test I did last night showed no signs of leak except at the part in my pic.

 

As I posted in another thread you can get a replacement for 20-25.00 for a 99 Chevy Express Van 3500.

 

That really doesn't help me or answer my question. I do all the work and actually like learning about the components of my truck,not just through money at it and hope that fixed it.

 

That's #WTY000020. Its the solenoid charcoal canister vent valve. It apparently does this:

 

thank you for some insight into what I'm working with.

 

Looks like the GM part no. is #25950499

 

I fully answered your ? in the other thread on this subject. You've got like 3 active threads going so kinda hard to keep up.

P0442 is that normally that valve, no I haven't smoke tested a 99-02 with that purge canister, but I have fixed the P0442 fault by replacing that part. These trucks aren't getting any newer, so you'll be tossing parts at it sooner or later, just the nature of the beast.

https://www.rockauto.com/en/moreinfo...353259&jsn=460

12.95 from Rock Auto

 

I have 3 threads going because the only answer I can get from a forum for this truck and by supposed mechanics and enthusiasts, is to just throw a part at it?

as I responded to you before,I need technical help. Not someone telling me repeatedly to just replace the part. But thanks for junking up my thread again

 

Good Luck