2003 Tahoe 5.3 flex has had an intermittent issue for about 1 1/2 years now. It only does it on really warm afternoons. I have a 30 mile commute home. Generally, I'll make it 1/2 way home before it just cuts out. I pull off with engine sputtering, but no throttle response. It will finally die and not restart for a couple minutes. No check engine lights. The engine will restart as nothing ever happened. Sometimes I make it the rest of the way, others, I have to repeat the process. It ONLY does this on hot days and in the afternoon...It runs like a top the rest of the time. It ran all winter without an episode as well. In 1 1/2 it has had a fuel pump, filter, crank sensor, and fuel pump relay. All initially appeared to fix it, but to no avail. Finally, it got so bad and frequent, that I had to be towed. HELP!!!!!