An Approach for Misfire Diagnosis in Critical Zones of the Operating Range of a High Performance Engine 2003-01-1058
The optimization of a high performance engine in order to achieve maximum power at full load and high speed can cause an unstable behavior when the engine is running at different conditions, thus making a robust combustion diagnosis for on board diagnostic EOBD/OBD II purposes (misfiring detection) particularly challenging. In fact, when a misfire occurs, its detection can be critical because of the high background noise due to high indicated mean effective pressure (IMEP) cyclic variability.
A partial reduction of the high IMEP variability had been achieved by optimizing control parameters of a new prototype high performance V8/4.2 l engine. Spark advance and VVT phasing maps had in fact been re-designed based on in-cylinder pressure variability (cycle by cycle and cylinder by cylinder) analysis.
In this paper the focus is the analysis of innovative misfire diagnosis techniques (such as joint time-frequency analysis of the engine speed signal) to make the new prototype V8 engine compliant with EOBD/OBD II regulations.
The instantaneous engine speed signal has been recorded during experimental tests while inducing various misfire patterns. Both test rig investigations (i.e., off-line data processing) and real time analysis for OBD purposes have been carried out.
The basic misfire detection algorithm has been modified by introducing a pre-processing of the experimental data, allowing to improve the effectiveness of the misfire detection also at higher engine speed operating conditions.
Citation: Moro, D., Ponti, F., Cipolla, G., Mammetti, M. et al., "An Approach for Misfire Diagnosis in Critical Zones of the Operating Range of a High Performance Engine," SAE Technical Paper 2003-01-1058, 2003, https://doi.org/10.4271/2003-01-1058. Download Citation
Davide Moro, Fabrizio Ponti, Giovanni Cipolla, Marco Mammetti, Luca Poggio
DIEM - University of Bologna - Italy, GT Powertrain - Ferrari SpA- Italy
SAE 2003 World Congress & Exhibition
Electronic Engine Control Technologies, 2nd Edition-PT-110, Electronic Engine Controls 2003-SP-1749