What Are the Reasons for Slight Vibration During Car Idling?
3 Answers
Reasons for slight vibration during car idling: 1. The engine mounts, which are the shock absorption system of the engine, are primarily responsible for absorbing minor vibrations caused by engine operation. When the engine mounts age, it can lead to vibrations during idling; 2. Ignition system failure, such as spark plug misfiring, can cause the car to vibrate at idle. It is advisable to promptly visit a 4S shop or repair shop for maintenance; 3. A dirty throttle body or excessive carbon buildup on the fuel injectors can also cause the car to vibrate at idle. Cleaning the fuel system is necessary, and it is recommended to use higher-quality fuel or add fuel system cleaner during regular refueling.
My old car used to have idle vibration issues. At first, I didn't pay much attention, but it became increasingly noticeable over time. The most likely cause was worn-out engine mounts - the rubber components lose elasticity over time, allowing engine vibrations to transfer directly to the chassis. Another common issue is carbon buildup, especially when the intake manifold and throttle body get dirty, leading to unstable air intake and causing the engine to run unevenly. Worn spark plugs can also cause this - misfiring makes certain cylinders perform abnormally. I've also noticed slight vibration when the fuel tank is nearly empty and the fuel pump struggles to draw fuel. I'd recommend first checking the engine mounts, then inspecting the spark plugs and throttle body. If these minor issues aren't addressed promptly, prolonged vibration can negatively impact engine lifespan.
Having driven many cars, I've found that idle shaking is mostly related to engine conditions. Carbon deposits are particularly prone to causing fluctuating air intake, which destabilizes engine RPM. Engine mounts are crucial for vibration absorption - if the rubber deteriorates or gets damaged, even minor engine vibrations become noticeable. When spark plugs have excessive gaps or electrode erosion, their ignition efficiency drops, and this is most apparent at idle. A clogged air filter restricting airflow is problematic too, just like a person having difficulty breathing. I make it a habit to regularly add fuel system cleaner and occasionally rev the engine to clear carbon buildup. For older cars, I always have mechanics check the engine mount condition during maintenance. While these minor vibrations may not immediately affect driving, prolonged neglect can lead to increased fuel consumption.
