car started briefly and then went back to not starting?

2000 BUICK LESABRE
3,730,030 MILES • 3.8L • V6
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JMB225
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Replaced Cam and Crank position sensors and ICM. After replacing each part, the car started briefly and then went back to not starting. Fuel is getting through the fuel rail back to the return line. No sparks from plug wires.
Aug 9, 2022 at 6:24 AM
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STRAILER
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Are they any codes? Also, we need to check the fuses. here are two guides so you can check and get back to me, test the fuses with the key on. There are 12 fuses that run the computer and fuel system of the car.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

and

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Here are the engine wiring diagrams so you can see how the system works and which fuses to check. Check out the diagrams (below). Please let us know what you find. We are interested to see what it is.
Aug 9, 2022 at 10:41 AM
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JMB225
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Ken L there are no codes. I will utilize the diagrams.
Aug 9, 2022 at 11:40 AM
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STRAILER
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Please let me know.
Aug 10, 2022 at 11:40 AM
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JMB225
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Hello Ken, sorry for not getting back with you sooner but I had other major distractions come up while working on my vehicle with one being a under slab water leak. I did go through the schematics and check each and every wire in the ignition system and was happy to learn all was good. I only wish I had taken a closer look at the ICM and ICM connector and I would have seen that pin P had gotten hot and melted the plastic which prevented it from getting a connection. I put a new connector on it and the car started right up. Thanks for offering me some info.
Sep 21, 2022 at 1:33 PM
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STRAILER
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Yep, slab leaks are no fun! Nice work on the car repair though, we are here to help, please use 2CarPros anytime.
Sep 22, 2022 at 12:07 PM
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JMB225
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Well Ken, I didn't want to start a new post because I have pretty much the same symptoms and problems. As mentioned, I went by the schematics and checked everything. This time I instantly looked at the ICM connector and saw that it once again melted around pin P. I cleaned it up and got a good connection and it's back running. Prior to it stopping all together after it warmed up it would run rough. I learned that the coil for 2 and 5 was not firing so I swapped the coils around and none worked in that position. I swapped the ICM, and the vehicle ran smoothly up until it got back to the cranking but won't start issue and at the point is when I cleaned the ICM connector and it's running in its current state. I need to find out why what is getting hot causing the connector to melt at pin P. I will include a video of the vehicle running rough before changing the ICM and smoothy after changing it. I will also include pics of both the original and new ICM connectors with both showing signs that they have gotten to hot. When it was running rough I did finally get a P1374 code for the CPS. I included pictures of both the original and new ICM connectors with both showing signs of getting hot and videos of the vehicle running rough before changing the ICM and smoothy after changing the ICM. It will currently start and run and idle smooth as seen in the video.
Sep 24, 2022 at 8:51 AM
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STRAILER
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Thanks for the images and videos, the connector could have a bad connection which causes it to get hot, but I have also seen non-OEM parts such as plug wires and spark plugs cause this issue because of high resistance. I would install AC Delco wires and spark plugs. It should fix the problem. Let me know.
Sep 24, 2022 at 10:38 AM
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