2001 no start no injector pulse during cranking

2001 4.0 automatic
Cranks over but will not start unless I pour gas down the intake and then it will start and run until I turn it off. Then it wont start again until I pour gas down the intake then it runs fine but when running the alternator is not charging.

This is what I have done/checked.
1. fuel press good at 45 psi cranking and running relay cks ok
2. replaced crank sensor
3. replaced cam sensor
4. cleaned all grounds and positive connections
5. asd relay/circuit cks ok
6. new pcm cleaned and checked connectors and pins
7. when cranking over have power to the injectors but no ground pulse to fire them
8. check wire between pcm and injectors... cks ok
9. All gauges on dash work
10. no fault codes
11. unplugged tps still wouldn't start
12. checked wiring between crank and cam sensors to pcm all cks ok
13. getting spark when cranking over
14. new battery

Could a bad alternator cause this? I am going to get it tested in the morning.

Trying to get it running to go on a four wheeling trip in TN (AOP) in April. Any help would be greatly appreciated.

The OBD-II Jeep REQUIRES constant and adequate voltage to start, and to run.

The alternator needs to be Load Tested on a test bench. Handheld testers are very inaccurate and will very often pass marginal alternators.

For 1996+ Jeeps, the OBD-II engine computer (ECU/PCM) re-boots, and the idle settings are deleted, when you: (1) let the battery run down by leaving the lights or radio on, (2) disconnect the battery for an extended period of time, (3) when the battery goes bad and needs replacing, (4) when the alternator is not properly charging the battery, (5) or when poor battery connections result in a voltage drop at the PCM or poor battery charging. Loose, corroded, or damaged battery cables or ground wires may also cause or contribute to the problem.

A faulty Coolant Temperature Sensor may also cause similar symptoms. Testing of the CTS is recommended as part of the diagnostics. A poor ground at the ignition coil can also cause similar symptoms.

The reboot symptoms are: (1) having difficulties starting the engine without depressing the gas pedal, and (2) the engine will have a low idle and probably stall unless you keep your foot on the gas pedal. (3) The ECU will relearn the idle settings after a short period of driving and the engine will often start and idle normally.

Begin with basic trouble shooting of the start and charge systems. Remove, clean, and firmly reconnect all the wires and cables to the battery, starter, and alternator. Look for corroded or damaged cables or connectors and replace as needed. Copper wires should be copper color, not black or green. Do the same for the grounding wires from the starter to engine block, the PCM, the ground wires at the coil, and the ground wires at the oil dipstick tube. You must remove, wire brush, and clean until shiny, the cable/wire ends, and whatever they bolt to. Jeeps do not tolerate low voltage, bad connections, or poor grounds.

Had alternator check at 2 different stores it passed.
I have gone tru all the wires and grounds with a meter all ck ok no high resistance. The voltage at the battery and back of the alternator is the same. The coolant sensor cks good also.

Genuine Jeep crank and cam sensors ? It is well known that cheap OBD sensors, especially the ones with a "Lifetime Warranty" are often made from inferior materials, are out of specification, or simply are faulty right out of the box.

There is fuel and spark, but apparently no signal to fire the injectors. The PCM looks to the cranks and cam sensors to confirm engine cranking and to time injector firing. If it does not see the correct signals, it will not fire the injectors.

mopar sensors in both. If they where bad then why does it run when I pour gas down the intake?

Because your spark trigger is separate from injector pulse

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Question:

Will it fire if you spray some carb cleaner down the intake while cranking the engine?

Did you check to see if the reluctor wheel in the oil pump drive/cam sensor drive spins while cranking?

Replaced pcm again. Engine runs and starts everything cks ok.