I am having a similar problem that another member had with his '93 Suburban. My truck is a 1993 GMC Seirra pick up, 5.7 litre gas engine.
The engine has 345,000 kilometers (215,000 miles) It will usually start when cold and never stalls. After driving for a while then stopping the truck, say to go into a store for 15 minutes, it won't restart. If I crank it too much I'll of course kill the battery. I let it sit for about 30 minutes then it will start like nothing was ever wrong. I have replaced the cap, rotor, wires, ignition coil. Could this be the ignition module overheating?
Is the ignition module IN the distributor on these trucks? My poor truck has been parked for months. If I take it to the dealer they want $120.00 just to tell me whats wrong with it. Hope somebody can help.

check your fuel pump i had one that did the same thing the wiring harness inside the fuel tank was bad

When it won't start, you need to determine if it is getting fuel and spark. The Engine Coolant Temp sensor can also cause a hard start issue. If it is reporting a cold engine temp, the ECM will deliver too much fuel and it won't start and become flooded.

Fuel pressure specs are 9 to 13 PSI and look for a good blue spark.

//2000CAYukon