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Honda developed a new generation 1.6L diesel engine as a part of technologies for high driving performance and good fuel economy. This new engine is equipped on Civic (C Segment, 5 doors), launched as a new European model in 2013. This engine has some technologies achieving both good fuel economy and low emission, and met Euro5 emission regulation. And the Civic achieved CO2emission of 94 g/km in NEDC, a reduction of 14.5% in CO2 emission against the previous diesel engine of Honda. [1] This engine has the dual EGR system composed of HP-EGR and LP-EGR, one of the technologies introduced to increase fuel efficiency. In this paper, some issues for the dual EGR system control and countermeasures for them will be described. In order to control each EGR mass flow, two or more valves (HP-EGR valve, LP-EGR valve and intake throttle) should be regulated cooperatively.

As technologies for simultaneously maintaining the current high thermal efficiency of diesel engines and reducing particulate matter (PM) and nitrogen oxide (NOX) emissions, many new combustion concepts have been proposed, including premixed charge compression ignition (PCCI) and low-temperature combustion[1]. However, it is well known that since such new combustion techniques precisely control combustion temperatures and local air-fuel ratios by varying the amount of air, the exhaust gas recirculation (EGR) ratio and the fuel injection timing, they have the issues of being less stable than conventional combustion techniques and of performance that is subject to variance in the fuel and driving conditions. This study concerns a system that addresses these issues by detecting the ignition timing with in-cylinder pressure sensors and by controlling the fuel injection timing and the amount of EGR for optimum combustion onboard.

There has been strong public demand for reduced hazardous exhaust gas emissions and improved fuel economy for automobile engines. In recent years, a number of innovative solutions that lead to a reduction in fuel consumption rate have been developed, including in-cylinder direct injection and lean burn combustion technologies, as well as an engine utilizing a large volume of exhaust gas recirculation (EGR). Furthermore, a homogeneous charge compression ignition (HCCI) engine is under development for actual application. However, one of the issues common to these technologies is less stable combustion, which causes difficulty in engine management. Additionally, it is now mandatory to provide an onboard diagnosis (OBD) system. This requires manufacturers to develop a technology that allows onboard monitoring and control of the combustion state. This paper reports on an innovative combustion diagnostic method using an in-cylinder pressure sensor.