iv notice that sometimes at the end of a run when lifting off the throttle it will show 4* of KR and I'm not sure why looking for thoughts. time on log 6:43:02
thanks
Transitional throttle is always a "special case" and stuff
goes on that takes you off the "map" developed by
steady-state / "averaged" tuning methods.
Lifting throttle from high RPM puts you at a very low
MAP, high RPM condition that normal driving can't get
enough hits, to tune well. You'd expect high advance
and perhaps a drop out from PE mode, both encouraging
spark knock.
Cylinder heads' temperature may have spiked meanwhile
too, cooling system playing "catch-up"?
Sudden release of engine torque may also cause a little
"banging" (false knock) in the same way as sudden apply.
I would think false knock it would happen more steady but I've been wrong before. Maybe reduce my timing high rpm low map, I already thought that area seemed high i will have to look at it tonight
I looked at your log also and didnt see anything that would cause knock.
Your timing isnt that high, and really does not change just before or during the knock. AFR looks ok also.
I would suspect the exhaust hitting the frame somewhere on decel creating a noise that the sensors are picking up as knock.
I did notice that the Torque converter clutch locks up about the same time as you have knock also. Can you disable the torque converter clutch in scanner controls and see if the problem goes away?
Some other things you can try to determine if its real knock.
1. run higher octane gas
2. Remove timing in the area where knock is detected and relog again driving in the same way
I didn't see anywhere the exhaust would hit on decel. I will look back at some older logs and see if it has a pattern with the tcc locking up. If I don't see anything I will add some octane booster. I'm already running 91, best I can get here sadly
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