What Causes Shaking When Starting a Car?

[OEverly]

The reasons for a car shaking when starting are: 1. The throttle valve is too dirty or the fuel injector has excessive carbon deposits, causing the gasoline sprayed by the cold start injector to be largely absorbed by the carbon deposits; 2. Uneven distribution of positive pressure between the main and driven discs, inconsistent adjustment of the separation levers or uneven separation finger ends of the diaphragm spring, leading to asynchronous pressing times and uneven force on the pressure plate, causing it to tilt; 3. Weakened damping spring force, clutch torsional damping spring force, and clutch pressure spring force, resulting in cracks in the diaphragm spring; 4. Loose engine mounting or misalignment between the transmission shaft and the engine crankshaft centerline.