Shutting off after 5 minutes, will not start untill cool down

Everything ran fine until today, truck shutoff and I thought to add gas since it was low, still no response. I proceeded to replace fuel relay, fuel pump and filter and problem with it running longer than a couple minutes continued and would not start until a cool down period of 30 min. Or so. The engine would start with a shot of starting fluid/gas telling me there is spark but no gas until cool down or natural reset of loop.