Fast Transforms for Rapid Isolation of Misfiring Cylinders
871915
10/01/1987
- Event
- Content
- This paper presents a method for the isolation of misfiring cylinders in an internal combustion engine.The method is based on the measurement of the extrema of engine angular velocity. It has been shown that a number of indices can be derived from such a measurement, to provide an indication of engine performance degradation. In this study, an onboard microprocessor-based instrument samples the extrema of the engine velocity waveform in real time, generating an N or 2N vector representing each engine cycle, where N is the number of cylinders.The data is processed by matrix transformations which are designed to isolate specific faults and their intensity. The transforms are constructed in such a way as to yield a nonzero output only when a certain fault is encountered.The system is capable of detecting individual or multiple cylinder misfires, both complete and partial. Experimental verification has been carried out in a passenger vehicle.
- Pages
- 11
- Citation
- Rizzoni, G., "Fast Transforms for Rapid Isolation of Misfiring Cylinders," SAE Technical Paper 871915, 1987, https://doi.org/10.4271/871915.