Engine knocking and misfire cause a negative effect on the engine power and the exhaust emissions such as HC, CO and $NOx.$ They also cause permanent damages to the three way catalyst (TWC) system. And a heavy knock can cause severe damages to the engine itself, which gives more reason why it must be detected and corrected. This study introduces a new system concept for detecting combustion misfire and knocking using breakdown voltage (BDV) characteristics between spark plug electrodes. This system detects and evaluates the degree of combustion by measuring the breakdown voltage which predicts that the breakdown voltage depends on the pressure and the temperature.

1.
Williams, J., 1996, “An Overview of Misfiring Cylinder Engine Diagnostic Techniques Based on Crankshaft Angular Velocity Measurement,” SAE Paper 960039.
2.
Nonomura, N., Sugiyama, J., Tsukada, K., and Takeuchi, M., 1987, “Measurement of Engine Torque With the Inter-Bearing Torque Sensor,” SAE Paper 870472.
3.
Reinmann, R., Saitzkoff, A., and Mauss, F., 1997, “In-Cylinder Pressure Measurement Using the Spark Plug as an Ionization Sensor,” SAE Paper 970857.
4.
Eriksson, L., Nielsen, L., and Glavenius, M., 1997, “Closed Loop Ignition Control by Ionization Current Interpretation,” SAE Paper 970854.
5.
Auzins, J., Johansson, H., and Nytomt, J., 1995, “Ion-Gap Sense in Misfire Detection, Knock and Engine Control,” SAE Paper 950004.
6.
Raizer, Y. P., 1991, Gas Discharge Physics, Springer-Verlag, New York.
7.
Meek, J. M., and Craggs, J. D., 1978, Electrical Breakdown in Gases, John Wiley and Sons, New York.
8.
Martychenko, A. A., Park, J. K., Ko, Y. S., and Chae, J. O., 1999, “A Study on the Possibility of Estimation of In-Cylinder Pressure by Means of Measurement of Spark Gap Breakdown Voltage,” SAE Paper 1999-01-1115.
9.
Park, J. K., Martychenko, A. A., Ko, Y. S., Jo, M. S., and Chae, J. O., 1999, “The Misfire Detection and Intensity Interpretation Using Breakdown Voltage Characteristics,” SAE Paper 1999-01-2934.
10.
Heywood, J. B., 1988, Internal Combustion Engine Fundamental, McGraw-Hill, New York.