Fuel Pressure Problems

I have a 94 Jeep Wrangler(4.0 MFI). Recently it started to take several cranks to start the engine. Now once it gets to operating temperatures, it is extremely difficult to start after you shut it off. I suspected fuel pressure problems. Fuel pressure is at 28 psi with the vacuum line on or off of the pressure regulator. After installing a new fuel pressure regulator it remains the same. The vacuum lines do not have any leaks, blockages, or kinks. The engine runs fine above low idle. Once it warms up, it runs a little rough at low idle after sitting still. Any suggestions.

It could be the crankshaft position sensor.
Search this site. There are alot of posts about it.
Mine was taking a couple extra cranks to start and that fixed the problem.

The CPS has nothing to do with the fuel pressure. You should have 45 psi with key on, not running. I bet your pump is about to go bad, or you have a crappy filter. Likely the longer and hotter your pump is running, the less PSI it can supply. You should have over 45psi while at idle.

Thanks. it was the fuel pump.