What causes unstable idle speed in Chery QQ3?
1 Answers
The reasons for unstable idle speed in Chery QQ3 are as follows: Spark plug failure: Weak spark caused by individual spark plug failure. Spark plugs can also accumulate carbon deposits, which can be cleaned to restore their activity. However, some spark plugs may experience performance degradation as they near the end of their service life. Fuel system blockage: Blockages in the fuel system, particularly in components like fuel injectors, or faults in the intake manifold. When fuel injectors are blocked, it can lead to insufficient fuel supply pressure, resulting in poor fuel atomization. This causes an imbalance in the air-fuel mixture and incomplete combustion, leading to related fault symptoms. Related sensor failure: Failure of related sensors can prevent the ECU from accurately controlling the air-fuel ratio. Common examples include faults in the coolant temperature sensor, oxygen sensor, and throttle position sensor. The coolant temperature sensor is typically installed on the engine block or cylinder head water jacket, directly contacting the coolant to measure temperature and provide reference data to the ECU.