가솔린 엔진의 시동시 엔진 제어변수가 배기가스온도 및 시동안정성에 미치는 영향

Keeping up the high exhaust gas temperature in a cold-start period is very crucial to improve emission performance in an SI engine, due to the enhancement of catalyst performances. In this study, engine control variables such as ignition timing, opening rate of idle speed actuator and fuel injection duration were changed by using programmable ECU at engine start to find out the trends of exhaust gas temperature variations and stability of engine start operation. Through the study, it was shown that decrease of pseudo fuel-air ratio increased exhaust gas temperature, but deteriorated stability of engine start. These two parameters become coincidence at 0.7 of pseudo Fuel-air ratio.