I have been trying to solve this for 2 weeks. When cold 7 psi- runs great. Within 15 minutes pressure drops to 3 psi and within 30 minutes it drops to 0, and the car dies. If I let it sit for 20-30 minutes pressure come back up and it runs fine and then it cycles back to 0.
So far I have replaced the electric fuel pump and main fuel filter, and removed an extra filter at the carb. I do not hear a rush of air when I open the tank fill, so I dont think its vaccuum in the tank. I am wondering if the tank intake has a screen and its getting blocked in the tank? Other ideas to look into? thanks peter