Abstract
In this study, the cause of the acceleration failure of Hyundai Motor's 2.0-liter CRDi engine was analyzed. We tried to find problems through MDA (Measuring Data Analyzer) based on data such as vehicle speed, air intake, and air-fuel ratio obtained during the actual driving process. As a result, it was analyzed that the failure of the EGR valve exceeded the NOx emission standard and caused a decrease in engine output. Through this study, it is possible to reduce the time and cost of unnecessary maintenance and repair, and it is expected that a rapid cause analysis will be possible in the case of new failure diagnosis in the future.