Engine stumble and stalls, not DTCs?

2010 KIA OPTIMA
110,000 MILES • 2.4L • 4 CYL • 2WD • AUTOMATIC
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GLWJR
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  • 2 POSTS
I will be driving, and the engine will hiccup. Sometimes is will be fine afterwards, and just keep driving. Other times it will feel like it running on two or three cylinders, the check engine light will be on but still won't populate a code. I can turn off the ignition and it will start back up and be fine. Sometimes when I pull over it will stall. Attached is a video of what the engine sounds like when it acts like all cylinders are not firing. The problem is not an ignition coil as they have been replaced.

Any ideas?
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Jul 21, 2023 at 5:01 PM
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STRAILER
  • ✓ASE Certified Mechanic
  • 54,832 POSTS
  • ASE Certified Mechanic
It sounds like the PCM is going out, I would remove it and send it out for testing or get a rebuilt preprogrammed unit. Here is the location so you can check it out, please check the electrical connectors as well. Check out the images (below). Please let us know how it goes.




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Jul 22, 2023 at 3:28 PM
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GLWJR
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Hi Ken, thank you for the reply and the idea. Any suggestions on where to send out for testing?
Jul 22, 2023 at 3:38 PM
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STRAILER
  • ✓ASE Certified Mechanic
  • 54,832 POSTS
  • ASE Certified Mechanic
Not off the top of my head, hit up Google and then check their reviews, which can tell you if the outfit is any good or not. Let me know what happens.
Jul 23, 2023 at 1:56 PM
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