P1441 EVAP code

Last week I got a Service Engine light with a P1441 code on my 2001 Suburban 5.3... "EVAP system flow during non purge event". I replaced the purge valve about a year ago due to another code. I pulled the line from the valve, stuck a hose on it and tried to blow through it. I couldn't really get any air through, but I thought it might be an intermittent failure of a cheap aftermarket purge valve, so I replaced it again. The code came right back. I had also ordered a vent valve a while back and never put it on, so I went ahead and did that. It also has a fairly new gas cap. The code came back again.

What are my options at this point? A hole/split in a hose? A wiring issue? A fuse? Fuel tank pressure sensor? Before I spend a lot of time trying to locate a leak, are there any other easy things to check?

It seems to run fine, but the exhaust maybe smells a little bit rich.

I would start here:

Welcome to your first post on the forum.

Do what @99Sierra2500 said. Stop throwing parts at it. That year, the problem is likely related to clogged lines and a charcoal cannister needing replacement. When the system has no CEL, what is your "fill up the tank" procedure? SHOULD, put the nozzle all the way in, fill on the slowest speed and when kicks off, pull the nozzle out and hang it up.

On my 2005 Tahoe Z71, I knew that the system does not last forever and it can $5 bill and $10 bill you to death. I did the fuel pump and everything in that area and forward, all at the same time. Big job but piece of mind is great.

Go thru the diagnostic procedures, listed above and use quality components, when available,

I checked power to the purge valve and it seems to be correct. I also plugged a smoke machine into the end of the line where it attaches to the purge valve. The smoke all exited from the vent valve. From what I understand, that valve is intended to be open when not powered, so it makes sense that smoke would come out. It also seems like that sort of rules out a clog in the main vapor line since smoke didn't have any issue running the full length of the line.

So that most likely leaves a saturated/faulty canister, a faulty fuel tank pressure sensor or a random short in a wire. I'll keep exploring, but I'm starting to lean towards the canister being the issue since I'm smelling rich exhaust and/or fuel. Although, I haven't had an issue with the pump shutting off while I'm refueling.

Update: On my way home yesterday, the engine light went off. Now I'm pretty sure I don't smell fuel anymore, either. So I'm thinking either replacing the purge valve or vent valve actually did solve the problem and I just had to drive it enough to get it back to normal. Or maybe it is a wiring problem what is going to be intermittent. Or maybe there was some kind of clog that cleared itself. Either way, it's going to pretty much be impossible to find the issue if it's not actively malfunctioning. I guess I'll just drive it and see if it comes back.