Ford Windstar dies please help

My 02 windstar started dying about 3 months ago. It may go a few days without dying and it may die 3 or 4 times in an hour. It will quit at any time going at any speed although it hasn't died at an idle yet. I have had it hooked up to a diagnostic computer it gives no codes or problems. The fuel pump, fuel filter, fuel pump relay, crank sensor, cam sensor, throttle position sensor and the PCM relay have been changed. And I checked the wiring the best I could. Has anyone out there had this problem and been able to find the cause. I would really appreciate some help.

Without any code(s), it is tough finding the problem.
I want to guess fuel, only because you have no codes......and I would expect something spark related to give you a code.
However, I am only guessing.
There are no sensors for fuel flow or fuel pressure.
However, there are a LOT of other things that it "could" be.
It would be interesting to try to monitor something, battery voltage as measured at the OBDII port....at the fuel pump...etc.

Are you talking about the port under the steering column? Or is there another port near the fuel pump? Sorry for the misunderstanding and thanks for the reply.

OBDII port under steering column.
Also monitor the voltage at the terminals of the fuel pump.
2 different locations......to monitor 2 different values (is the power on the OBDII port there when the failure happens and then......is there power TO the fuel pump when the failure happens).
These are checks that don't require new parts......and will verify or eliminate areas that are the cause of the problem.

Thanks for your help. I am hoping that I have some time to work on it this weekend. I will keep you posted.

RESOLVED - I had the alternator checked, it was putting out a good charge but the frequency was jumping up and down and causing something to go haywire and shut the engine down. I have driven it for a week since changing the alternator and have not had any problems.