Stephen,

If the ECT temp exceeds +40 C, engine RPM >2000, load >2.5ms, and the signal from the KS sensor is missing the KS code will be stored, and what happens after that is, Knock control is disabled, only initial boost pressure is permitted, ignition advance is reduced for safety reasons, an increase in the quanity of fuel injection to cool down the fuel/air mixture. I agree with you that the code should return several times before spending money and time to fix the problem. The first thing you can do that will only cost you time is to get up under the intake manifold and unplug the front and rear KS sensors and clean out the connectors, then put some die-electric grease on the connectors. It is very tight but patients and less than 20 cups of coffee will help. Should your sensors need replacing they come in a kit now with both sensors and a wiring modification, and the best way is to remove the intake manifold. With the manifold off you have room to do the wiring modification.