Why does the car vibrate after starting?

[MatthewAnn]

Here is an introduction to car vibration after starting: 1. Carbon deposits in the engine. When there is too much carbon deposit in the engine, it can cause poor engine performance and various malfunctions. Excessive carbon deposits inside the engine can cause the gasoline sprayed by the cold start injector to be largely absorbed by the carbon deposits, resulting in a lean air-fuel mixture during cold starts, making it difficult to start. Only after the carbon deposits become saturated with gasoline does the car start easily. After starting, the gasoline adsorbed on the carbon deposits is drawn into the cylinder by the engine's vacuum suction for combustion, enriching the air-fuel mixture. The engine's combustible mixture alternates between lean and rich, causing idle vibration after a cold start. Solution: Clean the fuel system and check if the idle air control valve has carbon deposits that need cleaning. 2. For vehicles with 3 cylinders or fewer, some vibration is normal. If it is more severe than usual, check the engine compartment for any abnormalities. Common symptoms include burnt spark plugs, excessive spark plug gaps, or loose spark plugs. 3. Sometimes, insufficient tire pressure or balance issues can cause the car to shake. In such cases, carefully check the tire pressure and look for any abnormal tire wear.

[VanAugust]

Having driven for so many years, it's quite common for a car to vibrate after starting, especially in winter or when the car hasn't been used for a while. The vibration is mainly because the engine hasn't warmed up yet, low oil temperature increases friction between internal components, or there might be an issue with the ignition system, like dirty spark plugs causing poor ignition. If the engine mounts are cracked or worn out, the entire engine support becomes unstable, leading to vibrations. Sometimes, not changing the oil on time can make it too thick, affecting performance. I've encountered these situations quite often. Letting the engine run for a few minutes after a cold start can reduce the vibration, but if it persists or becomes severe, it's best to take it to a mechanic before parts fail completely. Regular maintenance like changing the oil and spark plugs is crucial—prevention is always cheaper and less hassle than repairs.

[LeElijah]

I just bought a car not long ago, and the vibration after starting the car is quite annoying. After checking, I found that the engine mount wear is likely the cause. This part buffers engine vibrations, and when it's damaged, the car shakes badly. It could also be an ignition coil failure, insufficient or old fluids, spark plugs needing replacement, or a weak battery failing to start properly. I learned a little trick: after starting, feel the vibration amplitude. If it's slight, it's usually part of the normal warm-up process. But if the steering wheel also vibrates or the dashboard jumps erratically, get it repaired quickly to avoid increased fuel consumption or engine damage. Usually, pay attention to oil levels and air filter cleanliness; these details can prevent major problems.

[DelAlivia]

I've been using the car a lot lately, and the vibration after starting is usually caused by loose chassis components or aging belts. The condition of the engine mounts and drive belts can easily affect stability, and insufficient oil or ignition failure can also cause this. A simple method is to wait and see if it stabilizes after a cold start, and address any issues promptly.