dies while driving and may crank, may not.
 

My son has a 1995 ex auto with the 2.7. It starts right up when cold. It will run for about 10 minutes and then dies while driving. It seams the first time it does it, it will start back up. But if it dies again, I get nothing. All lights and radio work but no crank. I have replaces the main relay. If I let it sit for hour or so, it will start right back up. I have read so many forums and they all turn to the main relay. Thats why I'm here. TIA

From your description, you have a crank but no start. Please confirm.

First step in no start is to determine if fuel or spark is at the root of the problem. Try starting w/ throttle body cleaner or starter fluid (10 sec blast into air intake duct).

If engine starts briefly then spark is OK and fuel delivery is problem. If no start continues, then spark is likely missing and must be addressed.

good luck