New to forum got an 05 KJ that will crank with key an attempt to start but then won't. If you plant accelerator to the floor will start but runs rough and feathering throttle will keep going but it dies if you let off throttle the may or may not start the same way.

Things I've checked:
Spark-all coils are providing spark checked with plugs saw spark on all with my own
eyes

Injectors-Ohms are all 11.3 except one is 16, all are recieving power when back probed(have not checked with noid light when running)

Fuel pressure-checked with gage primes to 50 and holds when starting and when i get it to run as described before

Idle air control-removed and valve moves freely with little to no effort(unplugged and no change but will record code that it is not present),(havent checked any other way)

Tps-getting power will register on multimeter through full range

Replaced crank and cam position sensors with used sensors but was doing with old sensors already

Bought as a project that failed after shutting off in a parkinglot then began cranking as described.

Key on key off X3 will show codes on dash display. Pcm cleared daily due to interior lights are always on even after changing multiswitch on column, so cant leave battery attatched.

Any great KJ techs that can give me some next step ideas to check?

Update: took IAC out to clean due to being dirty and to see if might be a possibility. Plugged in but left out of throttle body and it idled, although high. Never had a code but may be part of my issue.

I see the same thing sometimes, never when the engine is completely cold, and not when turning it off and immediately back on, sometimes several times a day (frustrating!) and sometimes not for months at a time. When it happens, the engine has been off for 5-30 minutes.
I too did a fuel pressure check which held constant running and after turning it off as documented.
The issue persisted past a new engine.

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KJ 2005 Jeep Liberty Renegade
4WD, V6 Gas, Automatic, Tow Package

After several years, and several times last week, of this sporadic crank but failure to start issue, even after a new Jasper engine, I replaced the cranskshaft and camshaft sensors, Delphi brand. Replacing them was not too difficult. We'll see whether that fixes the issue.

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KJ 2005 Jeep Liberty Renegade
4WD, V6 Gas, Automatic, Tow Package