一辆东风日产阳光轿车(采用N16 2．0 L发动机),累计行驶12万km,发动机冷起动后运行到正常工作温度急加速时,进气管有回火现象,此时若将发动机熄火后很难再次起动。首先,热机时用示波器检查各缸的点火波形,正常;然后用故障检测仪对发动机ECU进行检测,正常;再检查冷却液温度传感器及其线路,正常。检查喷油器的喷油脉宽,发动机怠速时为2．5ms-2.9ms, A Dongfeng Nissan Sunshine sedan (using N16 2.0 L engine), total travel of 120,000 km, the engine cold start to normal operating temperature after the rapid acceleration, the air intake pipe tempering phenomenon at this time if the engine is turned off after the flame Difficult to start again. First of all, when the engine is warm, use the oscilloscope to check the ignition waveform of each cylinder, and then use the fault detector to test the engine ECU. Normally, check the coolant temperature sensor and its circuit again. Check the injection fuel injection pulse width, the engine idling at 2.5ms-2.9ms,