I have a 1991 Chevy G30 5.7 van. When I drive it for awhile and shut off for a bit, like to go eat, then come out it doesn’t want to start. It would eventually. I changed the fuel filter, pump, and now the pump relay and it doesn’t what to start. After I changed the relay it started and then I let it set and it doesn’t want to start again. It doesn’t sound like the pump is running now either. What else do I need to be checking?