Quote:
Originally Posted by biz77
What is it the DME is "overreacting" to?
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The DME reaction to knock sensor feedback is progressive. Normally it operates within a range than reduces timing in small amounts of say 1/4 degree. If knock sensor noise is above that range it overreacts with 3 degrees. This is when you know it's having a harder time honing in on the right curve which means combustion is becoming less stable. If it continues you get another 3 degrees. Finally if there is still no reduction in knock sensor noise after the two 3 degree drops it assumes you are experiencing preignition or something bad is happening and goes to limp mode / triggers ignition glow codes. The whole time it is learning long and short term trims by RPM, load, gear, etc.
Mike