Determination of engine misfiring using magnetoelastic torque sensor

A method for the determination of engine misfiring has been achieved with a magnetic-head-type torque sensor based on the magnetoelastic effect. Sensor signal treatment using fast Fourier transformation (FFT) is introduced into this method to detect the misfiring cylinders. It has been confirmed that the determination of the misfiring cylinders is successful experimentally in a multicylinder engine such as the four-cycle engine having eight cylinders. In addition, this method is superior in accuracy to the conventional method with rotation speed detection, as well as ease of sensor installation.