Could this be a problem with the crankshaft positioning sensor? Are there any other electronic control modules or sensors that could cause this intermittent problem if they are beginning to fail?

Possibly the crankshaft position sensor, bad fuel pump or bad fuel pump relay. Also there are other things that can cause this. Does the check engine light come on?

c.s. pos. sensor gives u a no fire when it goes bad. wouldnt run at all. check for good fuel pressure. check for good spark. i would still take it and have a diagnostic ran on it first. just because check.engine.light doesnt come on.doesnt mean its not storing a trouble code.

Thank you for the information...I will follow up on the fuel pump rely idea. We have already checked the the fuel pump, fuel pressure and good spark. We have taken it to a master mechanic and it still has the same problem. Thanks again.

Probably not the answer to your problem, but one of my customers had a Mustang that would run for 15 or 20 mins and die. He would wait and then it would start again. After going thru everything, it came down to someone stuffed toilet paper in his gas tank and it dissolved and would cling to the sock filter and cut off the flow of gas. Then release and go thru the same thing again. No big fix but was hard to find

I had a Pontiac firebird that would cut off going down the road.You had to wait for hours before it would crank. It wouldn't start with a jump either. Turned out to be a bad transmission sensor.