I have a 1996 Ford F-150 5.0 auto trans. 322,000 miles. Been having some issues with it after it set up for a little while with a bad transmission. I could go out and crank it up no problem, then sometimes after running it for a little bit it would die, even driving down the road. Try starting it back up, it would just spin. This was a suprise to me because after all the years and miles I've put on this truck I have never once had any problem whatsoever with it starting. It would just spin! It's firing at the cool, and there is fuel pumping all the way to the fuel rail. After letting it sit for about an hour or longer it will start right up no problem but then eventually do the same thing. Any advice is helpful thank you!

 

It seems to be something is failing when it warms up. My first guess would be ignition. Does this engine use the TFI module screwed to the base of the distributor? There was a class action suit against Ford over that. They tend to fail from the heat in that area. One of the failure modes is the engine dying when it gets hot, then seeming to work normally after it cools down.

I moved mine to another part of the engine compartment:

https://picasaweb.google.com/1155523...7MustangEngine

 

Pull codes I bet there will be something flagged... and yeah it'll probably be ignition related. The TFI module on a '96 will be on the fender in a headsink, that could still go bad but it could also be the PIP module inside the distributor. Codes should point you in the right direction.