| The OEM timing maps specifiy that knock sensor closed-loop mode is disabled over 3200rpm. However, the way the ecu detects knock is via rpm-indexed knock-limit tables. It is these tables that indicate knock detection is available up to 4400rpm in high octane mode, and 4000rpm in low octane mode. The cylinder firing order of the VG is 1-2-3-4-5-6; and no two cylinders are ever firing at the same time. So the ECU knows exactly which cylinder is firing and listens to the knock sensor over the duration of that combustion event. It doesn't need to do any triangulation. The ECU detects knock per cylinder and calculates a single global timing retard/advance to be used by all cylinders. It calculates different values to be used in closed loop and open loop. It does not calculate different timing values per cylinder. The reason it detects per-cylinder is because it needs to accommodate for differences in the knock-sensors ability to 'hear' knock from different cylinders. #3 is right next to the knock sensor, whereas #6 is further away and since the knock sensor is essentially just a microphone, #3 is going to be louder than #6. The knock detection system needs to compensate for this which it does by having separate knock-limit tables for each cylinder. I'm confident this info is correct as I'm just explaining what the ECU is doing in the microcontroller code, and binary arithmetic doesn't lie :p
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