01XJ evap problems

My fathers 01xj has been throwing evap codes for a while now. Currenty I have three codes turning the check engine light on. P0441, P0455 and P1494. Incorrect purge flow, large evap leak, and leak detection pump pressure switch.

70k on the jeep. It started out with an incorrect purge flow and small evap leak code. I changed the gas cap, evap purge valve and leak detection pump with new oem ones. It was fine for a few days then my father got gas and the codes came back. I cleared them and made sure the cap was tight and all the lines were on and everything was plugged in. Now everytime he gets gas they come back. I am starting to notice a small fuel vapor smell but I cant find anyleaks. I check the usual rubber ends that deteriorate and they seems good. I brought the car to my work and hooked up the evap smoke tester we have and could find anyleaks anywere. Anyone have any ideas, Im stumped.

My father got gas today, light came back on. I scanned it and the same three codes popped up. Anyone have any clue...???

I just had to deal with this. I ended up replacing the grommets on top of the tank (for the vapor vents) and a plastic T where those lines come together and run to the canister. If you can't find it with a smoker, you may need to use a sniffer. You know like the 70s either smoke or sniff until you get happy.