What causes slight shaking when the car just starts?
2 Answers
Possible reasons include a dirty air filter, broken high-voltage wire, worn-out spark plugs, abnormal water temperature, or clogged fuel injectors. Here is some relevant information: Throttle carbon buildup: As the vehicle accumulates more mileage, carbon deposits can form in multiple areas, especially in the throttle. If the throttle is very dirty, it can obstruct air intake, causing the engine to struggle or barely power the compressor. This results in the car shaking when the air conditioning is turned on. Engine mount damage: Even during normal operation, the engine vibrates, including after starting the compressor. However, the engine mount filters out some of these vibrations, making them less noticeable. If the engine mount collapses or is damaged, the engine's balance is disrupted. Turning on the compressor may then reach a resonant frequency, intensifying the vibrations.
My car used to shake when starting, especially in cold weather, feeling like the whole car was wobbling. The most common reasons are aging spark plugs or a faulty ignition coil, where the ignition system isn't performing well, causing irregular engine ignition. Sometimes it's a fuel supply issue, like dirty fuel injectors or insufficient fuel pump pressure, leading to poor fuel delivery and causing the engine to shake as if it's about to stall. Excessive carbon buildup is also a big problem, as clogged fuel lines can result in incomplete combustion. Once, I delayed fixing it, and the shaking worsened until I had to replace the spark plugs, which solved the issue. I recommend starting with the basics—check the spark plugs first and use some additives to clean the fuel system. Don’t ignore carbon buildup; small issues can escalate into costly repairs if left unchecked. Regular maintenance of engine oil and air filters can help prevent these troubles.
