If the plugs look normal except the electrodes burned off then that is due to pre-ignition or detonation. Do you hear a pinging or marbles in a tin can when accelerating lightly?
If you have no codes then we may have an issue with the knock sensor. This is supposed to advance or retard the timing if it is knocking or detonating.
Also, you can run a couple cans of injector cleaner through the fuel and increase the octane for a couple tanks just to rule out a fuel issue.
https://www.2carpros.com/articles/how-a-knock-sensor-works
Are they all this way or just one cylinder each time?
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Wednesday, March 24th, 2021 AT 6:55 PM