I have a 1989 iron with the 5.7. When I first start it, it fires right up and runs as long as I'd like but with a high idle. After I shut it off and try to restart it, it won't fire again. Cranks over strong and is getting fuel. I have replaced the cap, rotor, plugs, wires, coil, ignition module. I know there's more. If the time is out on the car could it cause this? Thanks!

 

Check your fuel pressure after shut down to see if your injections are leaking and flooding your engine. Also ohm your injectors cold then hot.

 

The stock injectors are notorious for coil failure...especially when they are hot, so checking ohms would be a good idea.