2004 sportsman 700 efi acts like its vaper locking

2004 sportsman 700 efi acts like its vaper locking, I put on new heat resistant foil under and on the sides of the fuel tank. Helped some but after couple of hours plowing or running it starts to act up, let it sit for a while I can co back out and it runs fine. any ideas where I would go next i’m stumped