Why does the car idle shake in cold weather?
3 Answers
The reasons for car idle shaking in cold weather are as follows: 1. Severe carbon buildup inside the engine, which makes it difficult to start the vehicle and causes idle shaking. 2. Issues with the vehicle's ignition system. It is necessary to check the spark plugs and high-voltage wires of the vehicle. Abnormal operation of the ignition system can lead to this situation, resulting in idle shaking or difficulty starting the vehicle. 3. Unstable fuel pressure in the vehicle's fuel system. The fuel pump cannot supply fuel to the vehicle properly, leading to poor fuel atomization or failure to open the fuel injectors, causing cylinder misfire shaking or failure to start. 4. Faults caused by insufficient engine cylinder pressure. Due to time-related issues, the vehicle's engine has exceeded its service life and can no longer function properly, resulting in intermittent idle shaking. In such cases, timely repair at a service center is necessary. Regular inspection and maintenance of the vehicle are essential to prolong its service life.
Car idling shaking in cold weather may be related to the following aspects. First, the low-temperature fluidity of engine oil deteriorates, making it unable to quickly reach lubrication points upon startup, increasing friction. Second, carbon deposits in the throttle valve contract when cold, affecting intake precision and causing an imbalance in the air-fuel mixture ratio. Third, ignition system issues, such as excessive spark plug electrode gap or aging ignition coils, lead to decreased performance in low temperatures. Fourth, vacuum tube rubber hardens and cracks in the cold, causing air leaks and affecting intake stability. Fifth, battery voltage discharge capacity weakens in low temperatures, resulting in insufficient ignition energy. It is recommended to warm up the car for two minutes and observe. If the shaking persists, check the spark plug condition or use fuel additives to clean the fuel system.
The last time I encountered the same situation was on a morning when the temperature was minus fifteen degrees Celsius. Right after starting the car, the steering wheel shook so much that I couldn't even place my phone steadily, and the exhaust pipe sound was intermittent. The mechanic at the repair shop said there were mainly three reasons: the low temperature increased internal engine resistance, causing unbalanced piston movement; poor gasoline atomization led to incomplete combustion; and the most easily overlooked reason was the aging of the engine mounts, where the rubber hardens and reduces shock absorption. He taught me two methods to diagnose: if the situation improves after warming up the car for five minutes, it's a normal phenomenon; if the shaking persists, check the engine mounts and the mass air flow sensor. Now I use fully synthetic 0W-grade motor oil, and cold starts are much smoother.
