I'm having some trouble with evap tests failing and not running on the 99 venture.

Bear with me, I have some new scanner software. I'm still figuring it out. (Scan XL Pro)

The fault history shows weak vacuum , the large leak test and small leak have failed in the past.
Vent solenoid shows "fault"
Purge solenoid shows "fault"

Both circuits are "ok"

I'm thinking I have a hose fallen off, plugged line, or plugged filter. Is there even an evap filter or is part of the canister? I have been under it in the back and notice nothing obvious.

Any ideas or would more info be helpful?

Thanks in advance.

Pull the lines off and see if it is full of gas? (the charcoal canister.)

What if there is gas coming out of one line?

Gas coming out of what line?
To the OP. I would check the pass through connector under the drivers floorboard. Possibly the valve isn't closing because the connector is corroded.

I will keep that in mind along w/ checking the canister when I do attack this. Thanks.

A defective or loose gas cap will cause both these codes to show . I'd check that out before all else . Tighten it or replace it ( they're cheap ) and see if this takes care of the problem . It may take a few days of driving ( with the new cap ) before the light goes off or have your local parts store ( Autozone , Advance , etc. ) turn the light off with their scanner . Sometimes they will , sometimes not ! Good luck !

I had a similar problem years ago with my 1998. Turned out to be the fuel filler tube. It was so rusted it no longer sealed where the rubber met steel. Especially the smaller breather tube. When I removed the rubber hose from it most of the steel tube stayed inside the rubber hose. Replaced it with a new one from GM (I think it was $108.) Got rid of the reoccurring codes. Good luck.