Knock Threshold

Hey guys. I am confused about my knock situation on a Link Xtreme. Why ECU registering individual Cyl. Knock Trims while I am not exceeding my knock threshold?

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G'day Grisom. Can you post up the log file? Also wondering what frequency you're logging the knock level at?

I would like to see the map & log also. What are the individual cylinder knock levels showing?

Zac, Adam,

For my SR20DET engine and stock knock sensor I am using 6kHz.

Before I made this post I had no idea that I can see individual cylinder knock levels. Also I assume that I have to much overall knock sensor gain. I have no way to audibly hear the knock to double-check. What do you think guys?

Yeah looking at individual cylinder levels you can now see why it is retarding. Definitely need less overall gain as you are seeing knock levels over 1000 in there which is getting near our max. Also you should update firmware to the latest as there were some improvements made to knock control in 5.6.5. You really need audio knock detection equipment to tune the knock control system properly.

Adam,

Thank you. So looking to these individual knock levels of 1000 can I assume that it was knocking on these particular cylinders?

Thank you. So looking to these individual knock levels of 1000 can I assume that it was knocking on these particular cylinders?

We dont know how you set/tuned the knock threshold so couldnt say whether it is actually knock or not in this log. You would normally run the engine under various loads and speeds using conservative ignition timing so you can establish a baseline noise level, then set your thresholds somewhere above this level. Andre has a webinar explaining the general process quite well if you havent seen it: https://www.hpacademy.com/previous-webinars/049-setting-up-knock-control-link-g4-vipec/