In-Cylinder Measurements and Analysis on Fundamental Cold Start and Warm-up Phenomena of SI Engines 952394
A recently developed Laser Raman Scattering system was applied to measure the in-cylinder air-fuel ratio and the residual gas content (via the water content) of the charge simultaneously in a firing spark-ignition engine during cold start and warm-up. It is the main objective of this work to elucidate the origin of misfires and the necessity to over-fuel at cool ambient temperatures. It turns out that the overall air-fuel ratio and residual gas content (in particular the residual water content) of the charge appear to be the most important parameters for the occurrence of misfires (without appropriate fuel enrichment), i.e., the engine behaviour from cycle to cycle becomes rather predictable on the basis of these data. An alternative explanation for the necessity to over-fuel is given.
Citation: Grüefeld, G., Knapp, M., Beushausen, V., Andresen, P. et al., "In-Cylinder Measurements and Analysis on Fundamental Cold Start and Warm-up Phenomena of SI Engines," SAE Technical Paper 952394, 1995, https://doi.org/10.4271/952394. Download Citation
Gerd Grüefeld, Michael Knapp, Volker Beushausen, Peter Andresen, Werner Hentschel, Peter Manz
Laser-Laboratorium Göttingen e. V., Volkswagen AG
1995 SAE International Fall Fuels and Lubricants Meeting and Exhibition
SAE 1995 Transactions: Journal of Engines-V104-3