In-cylinder Ion Sensing Opportunities

Why Do We Need Ion Sensing ?• For SI engine, to increase performance and lower fuel consumption,n,operating close to MBT timing is desirable– But it is limited by knocking– Accurate knock detection over all engine operating conditionsis required• To meet stringent emissions standard, misfire detection is requiredredfor all engine speeds for OBD-II• Deficiencies of current methods– Accelerometer sensor for knock detection loses accuracy athigh engine speed due to vibration noise and could not detectearly knocking– Traditional speed variation method for misfire detectionbecomes difficult for multiple cylinder engines (V6, V8) and athigh engine speed• Other sensors to accomplish these tasks have cost and technicallimitations• All these problems can be solved by in-cylinder ion sensing