| I found these documents (and more). Put on your thinking caps :) It explains how the knock system works in our ECUs. To sum it up, it's pretty damn complicated in the way it analyzes knock and our ECUs do limit knock per cylinder, not the overall engine timing. That's why when knock occurs you don't see a change in overall timing. I was doing a lot of experimenting and research with the knock circuit and I could see a change taking place between ignitions with a scope while simulating knock but couldn't get a change in timing. I was going to make a video of it but because simulating a knock is so different than actual knock the signals I could see changing were to sporadic for someone to make out by just watching a video. It was something you had to keep at and look for changes here and there. Banging on a knock sensor just wasn't producing anything that was video worthy. I also found tuners on other forums who talked about how you can't do the "bang on the knock sensor and watch the timing drop" test with our type ecus like you can with some of the good o'l Chevy and fords. The info.
[ http://www.maximusdvd.com/mytwinturbo/tech/US5121729.pdf ] [ http://www.maximusdvd.com/mytwinturbo/tech/US5404854.pdf ] Here is another good knock system I found too.
[ http://www.phormula.co.uk/Default.aspx ] Video of it working here.
[ http://www.phormula.co.uk/Player.aspx?clip=KS-3Demo&title=Demonstration%20-%20KS-3%20Knock%20Analyser%20and%20Knock%20Analyser%20Pro ]
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