What Causes Idle Vibration When Running the AC in Winter?
3 Answers
The reasons for idle vibration when running the AC in winter are: 1. Dirty throttle body; 2. Issues with the ignition system; 3. Excessive compressor pressure; 4. Engine carbon buildup or aging. The solutions for idle vibration when running the AC in winter are: 1. Clean the fuel system and check if the idle speed motor has carbon buildup that needs cleaning; 2. Inspect the spark plugs for excessive carbon buildup and replace them if necessary; 3. Check the fuel pressure and replace components if needed; 4. Replace engine mounts or other aging parts. The functions of the AC are: 1. To regulate and control the temperature, humidity, air cleanliness, and airflow inside the car cabin to an optimal state; 2. To provide a comfortable environment for passengers, reduce travel fatigue, create good working conditions for the driver, and serve as a crucial ventilation device for safe driving.
I've always thought that idling vibration with the AC on in winter is quite common, as I've encountered it several times. The main reason is that turning on the AC increases the engine load. The moment the compressor starts, it instantly draws power, and since idle speed is already low, the engine RPM drops, making it prone to vibration. Additionally, in winter, the low temperatures make the oil thicker, leading to uneven combustion. If the spark plugs haven't been replaced in two or three years, they can cause unstable ignition, and excessive carbon buildup only makes things worse. I suggest starting with simple checks like inspecting the spark plugs and throttle body. Regular engine maintenance and cleaning shouldn't be overlooked, as ignoring this issue could lead to more severe vibrations and potential damage to engine components. If you can't handle it yourself, take it to a repair shop for inspection—safety first.
Buddy, my car does the same thing. In winter, when I turn on the AC at idle, it shakes like a massage chair. I think the main reason is that the engine suddenly has to carry an extra load—the compressor kicks in and consumes too much power, and the idle speed is too low to handle it, so it wobbles. In winter, the low temperature already affects the engine's performance, the fuel doesn't burn as efficiently, and carbon buildup makes it worse. Worn-out spark plugs are also accomplices. The solution is pretty simple: regular maintenance to clean the engine, let the car warm up for a few minutes before turning on the AC to reduce the load. Don't cheap out on low-quality fuel, and replace the spark plugs when needed—it'll save you a lot of hassle.
