New motor will crank, but won't start

T_1776 said:
Well I feel like a bit of a fool, but I didn't realize that the ASD relay also killed power to the coil after 1-2 seconds of turning the key... I had my wife turn the key while I checked and sure enough, I get 12.5V-13V for a short time and then it drops. I went back to the crankshaft position sensor and verified that I was getting 5V to the sensor. But... I unintentionally hit the sensor wire as well and was surprised/scared when I saw that I was also getting 5V from the signal wire as well! From my understanding, I should see something from the signal wire only while cranking due to the way the sensor operates, but I'm getting 5V from both the supply and signal wires with the key on (not cranking). I figured there had to be a short somewhere so I traced the wires back to the PCM with no obvious issues. Out of desperation, I opened the PCM as well to check the capacitors and/or for any burn marks in general, but no dice. I took pictures of the internals to be on the safe side, but I'm throwing in the towel for the night.

I can't thank you guys enough for the support and advice, it is greatly appreciated!
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The signal voltage switches the 5-volt supply on & off as the engine rotates.
 
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Daryl said:
The signal voltage switches the 5-volt supply on & off as the engine rotates.
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So I should be seeing 5V from the signal wire until I crank? I say from the signal wire as I pulled the wires off the connector and tested each one individually while grounding to the frame and I'm seeing 5V from both the supply and signal wires. I wasn't able to crank the motor when I tested these wires, but if this is correct then I should see the 5V from the signal wire drop out/lessen whenever the slots on the flywheel pass the sensor?
 
T_1776 said:
So I should be seeing 5V from the signal wire until I crank? I say from the signal wire as I pulled the wires off the connector and tested each one individually while grounding to the frame and I'm seeing 5V from both the supply and signal wires. I wasn't able to crank the motor when I tested these wires, but if this is correct then I should see the 5V from the signal wire drop out/lessen whenever the slots on the flywheel pass the sensor?
Click to expand...
Your meter won’t react quick enough to see the change when cranking the engine, you need to rotate the engine by hand with the KOEO (key on engine off) method.
 
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Daryl said:
Your meter won’t react quick enough to see the change when cranking the engine, you need to rotate the engine by hand with the KOEO (key on engine off) method.
Click to expand...

I gave this a shot and and no change in the voltage reading. I checked it with both the signal and supply wires to see if maybe something got crossed and while cranking I can clearly see the notches in the flywheel pass the sensor with no change in voltage. Both supply and signal stay steady at 5.15V. I did buy a cheap crankshaft position sensor ($25 on amazon) so I guess the sensor could be garbage. But trying to avoid throwing parts at it, as I've been doing lol
 
Finally got the Jeep running late last week! The issue ended up being that junk crankshaft position sensor I bought off Amazon. Picked up a Duralast (I know, still not the best, but better than what I had) and installed it, fired right up.... I have since installed a new catalytic converter and a pair of O2 sensors. Still runs a little rough, but I know there are a couple of pretty bad vacuum leaks which I'm suspecting may be the culprit. Overall, put just over 50 miles on it since and all is good. Now I've got the Jeep fever and want to pick one up for myself! Thank you to everyone who helped me sort this out!!
 
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