I ran injector cleaner a couple times in the tank. When I had them out I talked to a mechanic about cleaning them because they have a machine. It was going to be pretty expensive, he didn't think it would fix the issue, so I didn't do it.

For now I'll just keep running them.

 

Think I figured mine out. I put a permanent fuel pressure gauge on today. Pressure drops immediately after priming no matter how many times I prime. And it drops FAST. Guess it'll get fixed whenever the fuel pump craps out. Got 199k miles on it. Holds constant 44-45 psi idling

 

check valve on the pump failed

that would be hard to start all the time, not just when hot

 

It is always hard to start. Sometimes it starts up faster if I recently shut off the motor. Like 5-10 minutes after. Don't mean to hijack. Sorry OP. Check your fuel pressure

 

Right. But the OP says his is only hard to start after its been running recently.

 

I have a 2001 Grand Cherokee. .. every now and then this happens to me. I can tell when its going to act up when it doesn't start on the first crank. Sounds as if it got flooded with fuel and makes you wonder if its going to start on the 2nd try but it fires up if not on the 3rd try and cleans itself out lol... doesn't happen every day but maybe once a week or so like it has a mind of its own. I thought maybe crank sensor at first but don't think so!!! If its not broke its hard to pin point but im with yall could just be a leaking fuel injector and wet the plugs when 1st attempting to start from fuel in the cylinders.

 

Did they change over to 4 hole injectors in the early 2000s or late 99 4.0 litres ?

 

Could it be the anti theft system dis abling the ignition system intermittently yet the injectors are spraying the cylinders while cranking and that wets the plugs ? I haven't looked into the anti theft wiring or how that operates if it controls fuel or spark.

 

Just wanted to update this now that I have a definitive answer. Had a bad injector after all. ehall nailed it. Guess I just needed it to get worse before I could see that it was leaking. Anyway, got a new set off ebay and now it starts like a boss every time. So satisfying!