I hope I can explain this well enough. I recently finished a 5.3 swap in my 85 k10 and it runs great unless it sit for awhile idling. then it acts like it runs out of gas and dies. On top of that if you turn the key on after it dies the fuel pump wont turn on and you have to wait a minute or so before it turns on again and it will fire right up again and not miss a beat. This only happens at an idle because i drove it about 10 miles with no issues. I hope i explained this well enough and if any one has any input i would greatly appreciate it.
Thanks,
Travis