car stalls when hot out, PLEASE HELP!!!

[89saleen388]

i have an 89 5.0 and my car will run and idle fine if it is below about 65 degrees outside. If it is hotter than 65 outside then after my car is warmed up it will usually die during idle, and will not start for about 5 min. and then it will fire back up run fine for a little bit then die again and so on......

i replaced the ignition module, and that did not help..

i can hear the fuel pump running, and pump up right after it dies..

i had a shop look at it but they could not find anything wrong and since it is cold out again, the problem will not present itself. they said to bring it in when it acts up again....

does anyone have any ideas or suggestions on what the problem might be???

thanks for the help