2000 silverado vapor lock?

well my silverado once in a blue moon dont want to start ,will turn over but acts like its flooded or something,i wait a few min. and it will crank fine,i changed fuel filter,i even cleaned map sensor,and for a while did great ,so then i bought new one did fine for a while,and now its doing it again,seems like it does it when i drive the mess out of it and dont let it idle a while in park before shutting it off,wonderig if any one else has the same problem,and if its vapor lock or something ,the wierd thing is that i had another 2000,silverado,and it did the same before i got rid of it,and i use good gas?

you might wanna try checking your fuel pressure regulator......its a common prob on these trucks and a fairly inexpensive fix....it was the culprit on mine...