Comptiateck

having issues with my 1996 Odyssey. No cell light comes up and van drives great but losing fuel. The smell of gas is coming from the fuel tank gas cap. every time I open up the cap alot of air and gas spits out. this only happens when the van is turned on. if I open it and let the crazy amount of air (not the normal from heat temp build up) out and close the cap again a few seconds later open up again and air comes out again. I replaced everything in the Evap system (including gas cap from a friends honda) except the canister but not sure if that's even the issue or is it ? anyone have an idea ?