1994 Chevy Astro stops running when outside temp is 100 deg

My astro van stops running when the outside temp is 100 degrees or more, It will start and when driving
about ten minutes this HIGH pitched sound starts and it will shut off, like it's starving for fuel.
It can barely start then when you gat it started and
start to drive it shuts down. I.M at a light and got
it started and had to put in nuetral then drive and
press gas pedal down as far as it goes then when it starts to go it stops like it's vapor locking or the fuel
pump stops working(No fuel getting in the line).
The high pitched sound gets even louder as the outside temp gets higher.I live in Las vegas and last
week it was only "100" and it did it a few times.
this week it's 108-106 out and I barely made it home almost got hit in traffic cause it just stops. PLEASE PLEASE help with an answer, and possible solution.
THanks-
From:TOO HOT IN VEGAS~~~