code P0300, flashing Check Engine Light?

2006 HYUNDAI AZERA
180,000 MILES • 3.8L • V6 • 2WD • AUTOMATIC
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CARLSP
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Car starts fine but then idles and runs really rough, The CEL is flashing and the only code I get is P0300. My question is, where do I start looking to find the cause of this random misfire? The oil cap was loose and so all the oil sprayed out over the engine. Drained out the oil and replaced it along with new filter. The oil that came out of the car was really black, very thick, almost like molasses, and smelled bad.
Feb 16, 2025 at 11:04 PM
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STRAILER
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When the engine is running does it make irregular noises? I would do a compression test to see if the engine is having a mechanical issue or upload a short video of the engine running so I can see and be able to tell what's going on.

A P0300 code indicates a random/multiple cylinder misfire detected.

Here is a guide to help you understand engine misfires:

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

and

https://www.2carpros.com/articles/how-to-test-engine-compression

Once you go over these guides or send the video, we can make a game plan on how to proceed.
Feb 18, 2025 at 10:15 AM