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Hi Dave!I apologize about the delay in getting back to you, I'm right in the middle of moving my garage from one bay to another (in the same building) so things have been hectic here for the past few weeks.The knock sensor system is very complex on these cars, I've honestly only brushed the surface of it. I have identified the knock modifier, and the knock indicator status bit. I've induced knock on purpose (increased timing) and saw the knock counts rise. There are 2 knock modifier tables (in the legend) that specify how much timing to pull (referenced by an RPM and MAP x and y axis). One table pulls a bit more timing than the other. It is possible that one map is for when the ECU detects the car is running non-premium low octane fuel and the other for when excessive knock is detected (failure of the EGR, overheating, etc).The biggest problem I am having is converting the raw data into something useful. In order to come up with a good conversion formula I have to sit out in the car with an accurate timing light and see what changes amount to 1 degree of timing. I simply haven't had enough free time to do this.I will try to dig a bit more into it for you tonight.-Matt
Hi Dave!
I apologize about the delay in getting back to you, I'm right in the middle of moving my garage from one bay to another (in the same building) so things have been hectic here for the past few weeks.
The knock sensor system is very complex on these cars, I've honestly only brushed the surface of it. I have identified the knock modifier, and the knock indicator status bit. I've induced knock on purpose (increased timing) and saw the knock counts rise. There are 2 knock modifier tables (in the legend) that specify how much timing to pull (referenced by an RPM and MAP x and y axis). One table pulls a bit more timing than the other. It is possible that one map is for when the ECU detects the car is running non-premium low octane fuel and the other for when excessive knock is detected (failure of the EGR, overheating, etc).
The biggest problem I am having is converting the raw data into something useful. In order to come up with a good conversion formula I have to sit out in the car with an accurate timing light and see what changes amount to 1 degree of timing. I simply haven't had enough free time to do this.
I will try to dig a bit more into it for you tonight.
-Matt
