I have a 2000 civic ex and I have a p1456 evap dtc .....leak detected I'm fuel tank area ....I've already replaced the fuel cap, so that's out of the picture. Here's my dilemma is there any way to pinpoint whether there is a leak in the fuel tank itself or if its the two way vent valve is defective without removing either. I know the pressure in the fuel system doesn't hold when you let the car sit for a few hours and try to turn it back on, because there is an extended crank time to get it started. Has anyone had this code and properly diagnosed it? I've found very little successful information regarding this specific code. Any help is appreciated thanks.