I bought the pump at napa but it was a mopar pump. Fuel pressure stays rock solid at 50 psi when this happens and as far as the fuel pressure regulator goes thats possible but where thehell is it? Ive been all over this motor and the only thing connected to the fuel rail is the inlet line. No return line, no regulator, nothing. Looks like a goffy setup actually.

 

I have a 98 Durango and having the exact same problem. Hesitation, like there is no fireing at all but then goes back to idle fine, sucking sound, when I tramp down the gas pedal everything goes back to normal for the remainder of the journey.