Wrangler 2.5 cranking but not starting


New Member
May 27, 2024
Need some help guys; I have a 4 cylinder 93' Wrangler 2.5 that had been having difficulties starting lately. Finally, it just reached the point where it didn't want to start at all, and not even showing the 'check engine' light.
The crankshaft sensor, MAP sensor and ignition coil have all been replaced. After that, the ECU was removed and all 3 of the capacitors were replaced with new ones (although only one of the old ones was damaged).
I also noticed that the pin no. 3 on the ECU plug connector (for the battery) showed voltage of 12V both hooked up and disconnected from the ECU. Furthermore, it's only when I disconnect the wire from the plug do I get the 'check engine' light on my display.
The connected plug pins 4 and 5 ( sensor ground and ground) according to the readings each show 7.5V. Any ideas what the issue could be? I've been busting my brain (and ass off) the past 2 weeks trying to figure out what could be causing this...
I agree with redbullet on the fuel filter. I would even go so far as to blow the lines while you have the filter out. Its kind of like clogged arteries in that they could be slowing the flow of fuel. If you are in a quiet enough environment you can turn the ignition on and listen for the fuel pump. If it is not quiet enough and you have a second person to help you can put a dowel or hammer or something between the tank and your ear and have them turn the key to see if you can hear the pump cycle. If it's the pump then you need to drop your tank and replace it.
I have been through this......Note number 10 on '92 and up and all that it controls.................

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