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View Full Version : Knock Retard GM.KNKRET vs Retard Due to Knock GM.KR


Gelf VXR
February 22nd, 2008, 12:19 AM
Why are they different? I'm logging both and getting different results????
Gelf VXR
March 7th, 2008, 06:10 PM
Anybody?

Below are the maps of both pids from a recent log with differing results. Max values.

I think GM.KR is the required pid, with GM.KNKRET picking up the same knock and more??

GN.KR
http://i5.photobucket.com/albums/y164/andysa1966/KR.jpg

GM.KNKRET
http://i5.photobucket.com/albums/y164/andysa1966/KNKRET.jpg
Gelf VXR
March 8th, 2008, 05:12 PM
Heres a stab in the dark, could GM.KR be spark reduction as a result of data recieved from the knock sensor and GM.KNKRET be spark reduction as a result of data recieved from the knock sensor combined with other PCM calculated knock reduction?

This makes sense as there is a band seen between 3600rpm and 4800rpm with the common value 3.87
Gelf VXR
March 9th, 2008, 03:18 AM
GM.KNKRET pid is the amount of retard to prevent burst knock from from i think {B1914} and its effect seen on this log, just after a change in TP. No GM.KR either.

http://i5.photobucket.com/albums/y164/andysa1966/KnockLog.jpg