No voltage on primary side of coil

1994 JEEP CHEROKEE
400,000 MILES • 4.0L • 6 CYL • 2WD • AUTOMATIC
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BREDMONDSON1
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I changed the ECM as recommended because of possible no grounding. Now, I still don't get a spark on primary side. The oil gauge doesn't show any oil pressure at all. What could be causing this? no start, no oil pressure?
Jun 7, 2021 at 4:01 PM
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KASEKENNY
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It is hard to say what component is causing this based on this info so we are going to have to run through the testing that I attached below to find out what the possible issue is.

Here are a couple guides that will help with this testing:

https://www.2carpros.com/articles/how-to-check-wiring

https://www.2carpros.com/articles/how-to-use-a-voltmeter

Let me know if you have questions but this should help narrow down what is causing the no start issue. Then we can tackle the oil pressure issue.

Thanks
Jun 8, 2021 at 5:30 PM
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BREDMONDSON1
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Well, I finally got it started. The connection with the radiator fan had to be disconnected. But once I did that, I started it but light blue smoke came from the exhaust. Then finally it quit running. On a restart, the starter just wouldn't kick in.
Jun 8, 2021 at 5:55 PM
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BREDMONDSON1
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It just spinned.
Jun 8, 2021 at 5:56 PM
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KASEKENNY
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Okay. It sounds like we just have an issue with the starter at this point and I don't think that is related to the blue smoke. The smoke may be just due to all the cranking you were doing.

I would remove and inspect the starter at this point and make sure the gear on the starter has not broken.

https://www.2carpros.com/articles/how-to-replace-a-starter-motor

This could be a greater issue but based on all this info, I think you are just getting a string of failures and on older vehicles like this that is not uncommon.
Jun 8, 2021 at 6:51 PM