What are the causes of idle shaking in new cars?
2 Answers
New car idle shaking may be caused by the following reasons: Engine carbon deposits: Excessive carbon deposits inside the engine can cause idle shaking after a cold start. When there is too much carbon buildup, a significant portion of the gas sprayed by the engine gets absorbed by the carbon deposits, resulting in an overly lean air-fuel mixture that causes difficult starting and shaking. Ignition system problems: Poor performance of the ignition system or faulty spark plug firing can lead to idle shaking in new cars. Unstable fuel pressure: Abnormal fuel pump supply pressure or incorrect readings and poor performance of the intake pressure sensor can cause vehicle shaking. It is recommended to visit a 4S shop to check whether the fuel supply pressure and intake pressure sensor are functioning normally.
I totally understand the issue of new cars idling rough. Just last week, I picked up a new car and encountered the same problem. After sending it for inspection, it turned out to be caused by poor fuel quality. Using low-grade gasoline led to clogged fuel injectors, causing uneven fuel supply to the engine and resulting in shaking. Another common issue is improperly installed engine mounts—those are the rubber components that secure the engine. If they're not fitted correctly during assembly, vibrations can transfer to the car body. Spark plug problems are also a frequent issue with new cars. My neighbor experienced this, with noticeable shaking during cold starts. Lastly, don’t overlook tire balancing issues. If the wheel weights aren’t properly attached during factory assembly, you might not notice it at low speeds, but there can be rhythmic vibrations when stationary. I recommend taking it to a 4S shop to scan for error codes—checking these areas first is a sure bet.
