车型:AuDI 2.2 E(机械喷射发动机)。故障征兆:热车时怠速转速过高(900 r/min～950r/min),且不稳定,发动机轻微抖动;排气管发出类似缺缸的“突突”声。检修过程:从理论上分析,引起发动机怠速不稳的原因可能有:空燃比不正确,进气管漏气,怠速控制阀及电控单元(ECU)异常,个别气缸压力不足,点火系不正常等。首先调整燃油分配器与空气计量板之间的混 Model: AuDI 2.2 E (mechanical injection engine). Symptoms: hot car when the idle speed is too high (900 r / min ~ 950r / min), and instability, the engine slightly jitter; exhaust pipe issued a similar lack of cylinder “bursts” sound. Maintenance process: From theoretical analysis, engine idle speed caused by instability may have: air-fuel ratio is not correct, into the air tube leakage, idle control valve and electronic control unit (ECU) anomaly, the individual cylinder pressure is not enough, the ignition system is not normal . First adjust the mix between the fuel distributor and the air metering board