So my passport recently ran out of gas and sat for 2 months before I finally got around to working on it, I got it to start by turning the motor over and holding the gas a little bit but once I shut it off, it won't start back up until a few hours later. While it runs the idle is high like a car usually does during a cold start but after it warms up the idle drops and drops all the way down to 300 rpm and then it shuts off, I've replaced the fuel filter and ran a fuel pressure test which measured 40psi with KOEO (Key on engine off) and while it ran it measured 40 psi but once the rpm dropped below 800, the gauge needle started to shake with the rest of the car and it dies.

 

check/clean the ICO.

 

I don't know what you mean by "ICO"

 

Idle cut off. will cause idle to go high on cold start, to start and die, or low idle below 800rpm. if you have over 100k miles sometimes a valve adjustment will cause the same.