Automated tuning of an engine management unit for an automotive engine

Abstract

Modern automotive engines are digitally controlled using an engine management unit (EMU) that is typically manually programmed using an engine dynamometer to obtain desired levels of power, emissions and efficiency. Closed-loop control of an engine dynamometer and EMU, combined with an overall engine tuning algorithm, is used to automate the tuning of the engine map for a four-cylinder engine. The tuning algorithm determines the air-to-fuel ratio necessary for each region of engine speed and throttle position to obtain the desired performance, automatically moving to each operating region in the map. Preliminary automated tuning results produce power output curves comparable with those delivered using the original manufacturer tuned EMU. At lower engine speeds data filtering is required and results in power outputs slightly lower than the factory-tuned engine. At higher speeds small improvements in engine efficiency, for equivalent performance, can be found. The research presented clearly demonstrates that engine tuning to a very high standard, equivalent to original equipment manufacturer engine performance, can he successfully automated, saving time and adding consistency to the engine tuning process.