got around to tilting my canister today and found no sign of split lines.....hoping to do my plenum soon, maybe thats why my CEL is comming on and off

 

Don't think plenum causes this. Separate system.

I had similar issue on step-son's ford. The hoses were porous, hence leaking. Due to the vapors, the hoses began to deteriorate.

Might want to double check those. I would probably replace them and see if the problem goes away. Hoses are pretty cheap.