Here's my wonderment. Mine: 94, 3.9, 4 wd. Put a new pump in the thing, have multiport injectors. New manufactures replacement pump was slightly different in that there was not a connection that looked like a metal bulb on top. Recall this was the output. Return on this set up also. Cold start, it starts immediately, almost a challenge to see if you can let go of the key quick enough. After it is warm, you have to crank it for 10 seconds or so to get it going, and the start is not powerful. I think the fuel is draining back through the pump, if there is a check valve in it. Once operating, all is fine, happy. Thought about putting a ball check in the delivery line near the fuel rail. I believe the fuel regulator is part of the pump on this set up.
Cheers from WA.

 

Maybe you should turn it on and wait a mo for gas to get to the TB before cranking? I pause a second after turning it on before I turn it over.

 

Yea, tried that like I was warming up a diesel. Minor improvement with 15 second wait.

 

Another idea came to me this morning. There may be a leak in your fuel system that is releasing the pressure in the line or fuel rail when it sits for a while. Edit the warmth of the motor or the day will vaporize gas more easily and that may be the why of it not starting as easily at lower temps.