1996 windstar stalling and not starting

the problem i am having is that while driving the vehicle (3.8 engine, 198,000 miles), it will shut off totally and not start. Upon checking i have spark at the plugs while turning it over on all occasions. There is fuel pressure at the valve on thr rail, not sure of how much. This stalling happens at anytime, while idling or at 50 mph. At times it will start up quickly and other times I have to let it sit overnight and then it will start. After it starts it runs normal, good idle and acceleration. The engine check light is off. It had to be towed home twice, it started the next morning both times. The fuel pump shut of switch on all occasions was depressed in the normal position.
Also the ps pump is making noise, after reading other complaints on this site does this have anything to do with the not starting? Any suggestions?
thanks

Hello

I would first off get a fuel psi gauge and check for psi during the no start. May be fuel pump related.

Regards


Dan