I have had this 1990 Chevy truck since it was new and now it wont
stay running for more than 5 or 10 minutes. Then it will die and wont
have any spark. Later on when it cools off it will run for another 5 or
10 minutes and die.

I have replaced the ignition module and the coil and it did not help.
This is with a 350 engine.

I am new to this forum and any imput would be welcome.

I have a similar problem with my 89 1 ton dump. The problem started when I changed my cap, rotor, wires and plugs. At first it only stalled momentarily, then started up. The dealer suggested replacing most of the fuel system, which I did. Long story short, I also replaced the water pump, thermmostat, ignition control module and a number of other small components that looked worn out (at the recommendation of the dealer). When I use the truck now, it stalls for approx. 30 minutes before it will start again. Sometimes I can continue to use it for a while and sometimes it will run for just a few minutes before it stalls for another 30 mins. Now that I see someone else has a similar problem, there must also be someone who has found the solution to it.