Injection start error, control difference

Hello everyone!

"The other day, I had a bad experience while overtaking. The engine control unit went into emergency mode, resulting in a significant loss of power and a noticeable, tractor-like knocking sound from the engine at certain RPM ranges." Just the other day again.
Today, I used a VAG diagnostic tool to read and clear the aforementioned error code (number 17656, engine code AHF, no tuning modifications). The fuel tank was full. Additionally, I cleaned the mass airflow sensor (MAF sensor) with alcohol. Then, a test drive of one and a half hours with a connected diagnostic tool revealed no significant anomalies and no new error codes.
The error can no longer be reproduced (hopefully, it stays that way).
What else do you recommend we try to get to the bottom of this issue? I'm not necessarily keen on replacing the fuel injector just based on suspicion.

What I also noticed is the values at full load, 3000 RPM for...
The air mass (group 10, field 1) and fuel injection amount (group 3, field 4) are barely reaching the lower target limit or are slightly below it. Should I possibly change the LMM?

Best regards,
Jörg



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