trouble restarting when warm

have a excellent condition 1991 Z28 convertible (305 TPI). 110K miles with a full tune 25K ago. when it's fully warmed up and i turn it off -then try to restart it, it may start once or twice (or maybe not) but then not again until it fully cools down. then it starts fine again. i've tried starting it as it cools down every 15 minutes but not until the temp gauge reaches 100 degrees will it start. any ideas? thanks (btw, i'm not a real gearhead but can do some minor stuff)

Does it turn over and not start or does it not turn over at all?

have a excellent condition 1991 Z28 convertible (305 TPI). 110K miles with a full tune 25K ago. when it's fully warmed up and i turn it off -then try to restart it, it may start once or twice (or maybe not) but then not again until it fully cools down. then it starts fine again. i've tried starting it as it cools down every 15 minutes but not until the temp gauge reaches 100 degrees will it start. any ideas? thanks (btw, i'm not a real gearhead but can do some minor stuff)

i had a very similar problem with my 90 3.1 V6. Turns out the ignition control module, which is inside the distributor was fried. It functions fine when cold, however, after the engine heats up, the heat makes its way to this module (by way of the metal the distributor is made of) and then causes failure. the module then returns to normal function after it cools down.

this could be your problem. (they are cheap enough and easy enough to replace anyway to see if it fixes your trouble).

just get a new one, make sure you get the clay-like paste that it is supposed to come with also. the paste goes on the underside of the module when installed to prevent direct contact with the metal of the distributor (and resulting failure from overheating again).