Lexus UX Hybrid Engine Knocking

I own a UX too (not the hybrid), and I've seen similar things recently. The 'knocking combustion' sounds like detonation or pre-ignition. Detonation is when the air/fuel mixture ignites after the spark plug fires, causing a shockwave. Pre-ignition is when it ignites before. Either way, it's bad. Have you thought about the fuel you're using? Lower octane can cause this, as it's more prone to premature combustion. Could ignition timing be related?

Thanks for the info! I appreciate the detonation/pre-ignition explanation. I usually use the recommended octane. Could the fuel still be the problem even if it meets the specs? And what do you mean by 'ignition timing'? Is that something I can check myself, or is it better left to a professional?

Even with the correct octane, fuel quality or storage can affect performance, however unlikely. 'Ignition timing' is the moment the spark plug fires relative to the piston's position. Incorrect timing can cause knocking. Diagnosing and adjusting it needs special equipment; it's not easy to do without it. Given the reduced power, jerking, smoke, and error codes, I'd see a qualified technician ASAP. Address potential detonation quickly to avoid engine damage. Repairs can reach 425€, so it's better to be safe.

I appreciate your advice and explanations. I've booked an appointment with a mechanic to check the knocking causes and ignition timing. It was indeed caused by deposits in the combustion chamber. Hopefully, this fixes it before it gets worse. Thanks again for your help!