Some data logs! Weird results. The only lift/knock event I have seen was with little throttle applied. There seems no reason for the 2 knock events that I had during my 30 min drive. I did stop for gas and heat soak could be the factor for that one. But the other?? There is also a WOT run to 60 and I had 0 KR even on the lift.

Spending a little more time with this I am not sure what I am seeing is true knock. I have found this. Interesting read.

http://www.zzperformance.com/blog/about-knock-retard-kr/

I believe that in these cases this not truly knock (detonation). But this is speculation at this point.

Maybe we should be taking another look at the PID/equation for this gauge. A lot of the new PID's were amazingly pieced together with parts from multiple sources, with great collaboration and clever reverse engineering but every once in a while a  gauge came with weird reading and often that showed a problem. Just saying what if?  On the other hand it does make sense that for me any way, the most aggressive tune gave me a 7 positive, 4 negative, my next most aggressive gave me a 2 positive, 4 negative, and now my stock file so far is reading 0 positive, 4 negative.

Quote from: Larrylu on August 07, 2014, 05:36:28 PM
Maybe we should be taking another look at the PID/equation for this gauge. A lot of the new PID's were amazingly pieced together with parts from multiple sources, with great collaboration and clever reverse engineering but every once in a while a  gauge came with weird reading and often that showed a problem. Just saying what if?  On the other hand it does make sense that for me any way, the most aggressive tune gave me a 7 positive, 4 negative, my next most aggressive gave me a 2 positive, 4 negative, and now my stock file so far is reading 0 positive, 4 negative.

I'm totally open to the fact it isn't accurate entirely.  The formula for this PID is something of a guess (even though it is a very simple formula).  I will do some more logging specifically on this parameter and see if I can get a Hex/binary reading that makes sense.  If I assume FORSCAN is correct I can see what values of knock correspond to what values in Hex and derive the formula.  I technically did this the last time and ended up with the A/2 formula but I will admit that Forscan can interpret knock in quarter degrees and you can't get there with A/2 so something is off.  It also returns at least two bytes (A and B) but the B value is always changing unless it actually sees knock.  Almost like it is a counter or something to tell you that the sensor is still working and then when it sees knock it read the "actual" value.  I don't know how else to describe what I'm seeing in the response from the car...I definitely would like to know for sure so let me keep at it and gather a few more sample points to at least see if this PID holds.  My challenge will be that I almost never see greater than 2 degree of knock...once I think I got a 3.5...can't hurt to double or even triple check as this is a pretty important variable.  Be patient with me though...My wedding anniversary was yesterday, my oldest turns 18 today and my 4 year old turns 5 on Sunday. 

I'm not sure that there is anything wrong with the equation. On my recent data log with FORScan it seemed to react the same way as torque.

Eventful calendar, ecoboostsho!  Belated congrats on your wedding anniversary, happy birthday to your oldest (voting age!), and upcoming happy birthday to the 5yr-old-to-be!

^^ what he said lol

Thanks guys...!

Sent from my XT1060 using Tapatalk

Happy all that stuff...busy time of year huh...
quite a few similar readings from people with similar tunes also, thinking the equation is solid, but I really have no idea...lol...

Thx for your efforts again

Quote from: ShoBoat on August 07, 2014, 05:06:30 PM
Spending a little more time with this I am not sure what I am seeing is true knock. I have found this. Interesting read.

http://www.zzperformance.com/blog/about-knock-retard-kr/

I believe that in these cases this not truly knock (detonation). But this is speculation at this point.

I know some of discussed KR on abrupt throttle lift.  I do not believe that is detonation at all.  Unless someone can provide a logical reason for spark knock under a closed-throttle and no load condition, I maintain the sensor is just picking up "noise" that is not spark knock and not harmful. 

Agreed. I have been logging for a few days now. I believe that KR we could be seeing is at least in my case directly related to IAT2. If it's above 60C I will get a bit of KR. In the area of about 2 or less. Last night after sitting at a long traffic light I did a 1/2 pedal run to the limit and had KR of 2 through part of 1st gear. IAT2 was at 67C.

Okay I think I've figured it out.   I did quite a bit of logging on the way to work with FORSCAN.  First I agree with ShoBoat...I typically only see maybe a blip or 2 of knock at part throttle but it does seem temperature dependent...with the outside temps in the 70s this morning and running at highway speeds I honestly had a hard time generating any knock.  If I let the motor heat soak I can see 2 or 3 degrees.

As for the equation it wasn't really far off at least compared to FORSCAN (sorry for anyone hoping it was if you've got a +7 reading).  After numerous logs and serial captures the PID does use both the A and B parameters in the equation.  The B is the 1/4 degree part...just took some thinking. 

I still need to go out and verify this but I believe this is close...The sign may be off though but either way it would only be off up to a 1/2 degree...

Signed(A)/2+(B/512)

This would result in readings from -3.75 to +7.25 degrees of timing added or subtracted accordingly.  The bad news in this is if you are getting 7 degree of knock I do believe the "reading" is accurate...it doesn't mean it's actual knock though...just that the knock sensor is picking up something it thinks is knock.  However if you go back to stock and the knock goes away I believe it was sensing real knock as opposed to the throttle body shutting etc...just my thoughts. 

Sweet, thanks. I'll give the new equation a try

I will also try the new equation and post results. I'll  try going back to stock and looking at kr numbers. Thx for all your help and effort on this. 

Just entered new equation. About to go give it a test. Hats off to you sir!