What are the causes of engine shaking and unstable idle speed?
1 Answers
Engine shaking and unstable idle speed can be caused by the following reasons and solutions: 1. Excessive engine carbon deposits: When there is too much carbon buildup inside the engine, the gasoline sprayed by the fuel injector during startup will be largely absorbed by the carbon deposits, resulting in an overly lean air-fuel mixture and difficulty starting. The vehicle will only start easily once the carbon deposits have absorbed enough gasoline to reach saturation. Solution: Regularly clean engine carbon deposits. 2. Air filter: Failure to replace it in time can lead to insufficient air intake, reducing engine idle speed and causing engine shaking. Solution: Replace the air filter. 3. Low ignition energy: During cold starts, the engine's internal temperature is insufficient, requiring the fuel injector to spray more gasoline to meet power demands. Fuel needs higher ignition energy, and increased spark plug gap can lead to reduced ignition energy, subsequently affecting performance and causing vehicle shaking. Solution: Replace the spark plugs. 4. Abnormal water temperature: High engine water temperature can cause ignition timing to advance, altering the air-fuel mixture ratio and thinning the engine oil viscosity (reducing lubrication). Causes of abnormal water temperature include insufficient coolant, a stuck thermostat, fan malfunction, or inaccurate temperature control switch readings. Solution: It is recommended to visit a 4S shop for inspection and repair.
