2000 xj 4.0

Problem: to start my jeep I have to press down on the skinny pedal and get the RPMs spinning around 3 grand and slowly set them down to idol while I turn the key or it will just turn over, start, then immediately die when it tries to idol.

Things I've already tested:

I pressure checked the fuel rail that goes to the injectors and it was all good, however I have not pressure checked the pump yet and from what I understand my year xj has no fuel filter.

Already replaced both the alternator and battery because they were both bad, and I checked them both under a load and they are good,

Cleaned all body and engine grounds of corrosion and dirt.

Checked mass airflow sensor and all throttle body connections for corrosion and resistance.

There is another odd thing happening, when I turn my key to the on position the relay controlling my auxiliary fan switches on and off which leads me to believe it is an electrical problem or possibly a PCM problem witch is related to the no idol problem.

Meanwhile I'm trying to not disconnect my battery because I have been running a 10 day inspection for the past 2 months and every time I disconnect it I have to drive to rid my system of the not readys

 

no idea what I could be but you should have a fuel filter

 

Fuel filter is a basic sock. It lives in the tank and is non-serviceable.

Next time it dies jump out and get the battery voltage with a multimeter. What shape are the cables in?

 

Already tested the battery and alternator voltage upon start, it's all good

 

Not on start, when it dies.

 

https://www.cherokeeforum.com/f2/idl...art-up-181378/