What are the causes of vehicle shaking during start-up?
2 Answers
The causes of vehicle shaking during start-up are: 1. Loose engine mounting or misalignment between the transmission first shaft and the engine crankshaft centerline; 2. The clutch is locked or has loose connections, and the clutch disc is severely worn; 3. Uneven distribution of positive pressure between the driving and driven discs, inconsistent adjustment of the release levers, or uneven diaphragm spring release fingers. The steps for starting are: 1. Insert the key, turn on the ignition switch, and start the engine; 2. Depress the clutch pedal, shift the gear lever into first gear, observe the surroundings of the vehicle, and release the handbrake after ensuring safety; 3. Lift the clutch pedal and start smoothly.
Starting shudder is quite common in my driving experience, with multiple potential causes. The primary culprit is often the engine ignition system – worn spark plugs causing unstable firing can make low-speed starts shake like a sieve. Fuel system issues like clogged injectors or weak fuel pumps lead to intermittent supply and imbalanced air-fuel ratios. A dirty mass airflow sensor restricts intake, making the engine struggle to breathe. For manual transmissions, worn clutch pressure plates or flywheels cause violent shaking during partial engagement; automatic transmission issues like faulty torque converters or shift modules result in jerky power delivery. Deteriorated engine mount rubber losing its damping effect transmits vibrations throughout the vehicle. I recommend starting with easily replaceable components like spark plugs or air filters, conducting 20,000-km periodic checks to prevent cumulative issues compromising driving safety.
