Hello Everyone, been a while I know - this last month I dusted-off EFILive and got back into tuning my truck, and am tackling spark timing issues/questions.... I am trying to dial-in my spark advance table, and eliminate part-throttle KR. I think I am seeing two KR issues, one is light KR under part-throttle driving (1-3 degrees), and the second is major KR (5+ degrees) under sudden load/demand or kickdown. The KR I am seeing is 'spikey' not 'sawtoothed' so I am guessing that this is more burst knock retard (?) rather than detonation, but I am not sure. To get a better idea of my issue, I logged the following PIDS:

GM.KR - zero, except for a single instance of 7-degrees under 1/2-throttle
GM.EST_BTM_DMA - zero the entire log
GM.EST_KRB_DMA - a dozen 'random' spikes of -1 to -3 degrees sprinkled about the whole log
GM.EST_XMSN_DMA - major activity, literally half of the driving was with 18+ degrees of retard

Questions:

What controls EST_XMSN_DMA (Trans Torque Reduction Spark Retard)? The torque management tables in my tune are all zero'd out, where is this activity coming from? I can see GM.SPARK PID affected by EST_XMSN_DMA, but this EST_XMSN_DMA retard is not included in GM.KR PID (I thought it would be?)

(log attached)Attachment 14324

Vehicle info - 2003 Silverado SS AWD, LQ9 stock with Paxton Novi-1500 @ 10-psi; EFILive COS3.

- Steve.