Reasons for Car Shaking at Idle Speed?

[Brayden]

When a car shakes at idle speed, it is usually due to issues with components such as the ignition system, oil pressure, throttle valve, or fuel injectors. Below are the specific causes and solutions: 1. Dirty throttle valve or fuel injectors: This is the most common cause of car shaking at idle. Excessive carbon deposits can prevent the fuel sprayed by the injectors from entering the cylinder properly, as most of it is absorbed by the carbon deposits. This leads to an overly lean air-fuel mixture, making the car difficult to start. After the car starts, the fuel attached to the carbon deposits is absorbed and burned, causing the engine's air-fuel mixture to become too rich. The unstable state of the air-fuel mixture results in car shaking at idle. Solution: Clean the throttle valve and remove engine carbon deposits promptly. 2. Unstable oil pressure: For this issue, it is recommended to visit a 4S shop for inspection, as professional diagnostic equipment is required. Items to be checked include fuel supply pressure and the intake pressure sensor. Solution: Check the oil pressure and replace any damaged components if necessary.