This 2006 Honda Accord V6 is running ROUGH at 205k miles.
Owner says it's misfiring at idle, and won't pass the State Emission Test with a persistent P0300.

Plugs and coils obviously didn't help.

Although I suspect what the issue is, let's PROVE it with scientific DATA before quoting the customer on the final repair procedure.

PHAD PRESSURE TRANSDUCER:
http://www.pinehollowdiagnostics.com/...

IVAN'S PICO WAVEFORMS:
https://drive.google.com/drive/folder...

2023 Upgrade LAUNCH X431 PRO3S+:
https://www.amazon.com/dp/B092894STV?...

TESLONG NTS500 Dual Lens Endoscope:
https://www.amazon.com/dp/B07SQ4FLYX?...

VAMPLIERS:
https://www.amazon.com/dp/B00LMOAYR2?...

Enjoy!
Ivan