The knock correction system is quite complex. The primary decision making factor is the knock sensitivity map, which is a general one implemented by nissan. Each engine will have its own unique signature. Using my tuning software, I'm able to generate knock sensitivity compensations based off of hundreds of megaytes of log data, producing a very unique knock signature for the engine which can be applied to help the ECU tell the difference between real knock and simply a noisy cylinder/engine.
Using limited log data can work to determine some of these thresholds, but the sheer size of the map and the conditions it covers makes it almost impossible to get accurate results from just a handful of logs.
Once the threshold(s) are crossed the ecu responds by pulling timing respective to how much the threshold is crossed. Timing keeps getting pulled until noise levels stablize. The ecutek knock warning simply flashes when the ecu has corrected the timing by a certain amount. Some tuners leave it at the default -3 degrees, some set it to -6, whereas others disable the feature.
Once the timing is pulled to around -9 correction, the ecu switches to a fail-safe mode map and the corrections can actually appear positive rather than negative.
The more corrections the ecu makes, the more power you will loose. This is becuase incorrect timing off by as much as 2 or 3 degrees will cause a loss of power that will remain until the ecu decides to advance the timing back once it thinks it's safe.
If anyone is interested in learning more or getting their calibration adjusted to be as perfect as possible, please feel free to reach out for assistance. I do all the tuning using data analysis software that I've developed specifically for doing various types of tuning. I require large amounts of data to produce effective results.
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