Working on what bill said. If you are modding your car you know the 4 cycles of your engine. on the power stoke for optimum power the spark plug lights up a few degrees before top dead center of the compression stroke. When you engine is knocking the gas being compressed ignites before the safe ignition zone of compression stroke. So to combate this the PCM electrically retards the spark. so the spark ignites farther into the compression stroke. This keeps your engine in one piece but you do loose power. Simple things can be done by you to stop predetination. You a higher grade gas. If you are boosted should be using 93 anyways. ON the 2000+ the 3.8 sometimes get carbon deposits which cause hot spots to start predetination. A head gasket but on wrong can cause an over hang in the cylinder causing a hot spot.
In short owning a boosted car turbo or blown you will always be fighting KR Check on ZZP'* tech articles some good stuff there.
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