What Causes Car Idle Vibration?

[Katie]

Car idle vibration can be caused by the following reasons: Severe engine carbon buildup: The most common cause of idle vibration is excessive carbon deposits on the throttle body or fuel injectors. When there is too much carbon buildup inside the engine, the gasoline sprayed by the fuel injectors during cold starts can be largely absorbed by the carbon deposits, resulting in an overly lean air-fuel mixture and making starting difficult. It is necessary to clean the carbon deposits from the throttle body and fuel injectors. Poor ignition system performance: Poor ignition system performance or faulty spark plug conditions can also cause engine idle vibration. Check if there are any faults in the ignition system and whether the spark plugs have excessive carbon buildup. If so, replace the spark plugs promptly. Unstable fuel pressure: If the fuel pump supply pressure is abnormal or the intake pressure sensor readings are incorrect, it can also lead to body vibration during idle. Inspect the above components and replace them if necessary.