故障现象一辆2008年生产的2.3 L天籁自动挡轿车,行驶里程约为12.8万km。据驾驶人反映,该车发动机故障灯常亮,起动困难;起动后,发动机怠速抖动;行驶中发动机偶尔会突然熄火,并且有时加速无力,而在加速正常时,会听到异响。出现上述故障现象后,该车曾在其他修理厂进行过维修,更换过火花塞,清洗过节气门体和喷油器等,但未能排除故障。故障诊断接车后首先试车。接通点火开关,发动机故障灯常亮,第一次起动发动机未成功,第二次起动了稍长时间才起动着机,此时发动机怠速开始抖动,将换挡手柄置于P Symptom A 2.3 L Teana automatic transmission sedan produced in 2008 has a mileage of about 128,000 km. According to the driver’s reaction, the car engine fault light is always on, it is difficult to start; after starting, the engine idles and jerks; while the engine is running, the engine suddenly turns off and accelerates weakly sometimes, and abnormal noise will be heard when acceleration is normal. In the event of the above symptoms, the car had been repaired at other repair shops, replaced the spark plugs, cleaned the throttle body and injectors, etc., but failed to troubleshoot. Troubleshooting After the first test car. Turn the ignition switch, the engine fault light is always on, the first start of the engine is not successful, the second start a little longer before starting the machine, then start the engine idling jitter will shift handle placed P