故障现象一辆原装进口日产风度轿车,出现发动机怠速抖动的故障。故障诊断首先验证故障现象。发动机起动着机几分钟后,怠速就开始严重抖动,而且发现排气管发红,像混合气过浓的症状;原地对发动机进行加速试验,加速时发动机提速缓慢,工作声音感觉发闷,急加速时进气管有严重回火的现象,类似混合气过稀出现的现象。经过询问驾驶人得知,该 Symptoms An imported Nissan graceful sedan, the engine idling jitter failure. Troubleshooting First verify the symptoms. The engine started a few minutes after the machine, the idling began to severe jitter, and found the exhaust pipe redness, like the mixture too strong symptoms; on-engine acceleration test, the engine speed acceleration is slow, the sound of the work feeling boring, Rapid acceleration of the intake manifold have a serious phenomenon of tempering, similar to the phenomenon of mixed gas appears too thin. After asking the driver to know that