What Causes the Car to Shudder and Jerk When Starting in First Gear?
2 Answers
The reasons for the car body shuddering and experiencing jerking when starting in first gear may include poor contact of the clutch lining, weakened damping spring elasticity, or uneven elasticity of the clutch pressure springs. Below are the specific causes and solutions: Weakened Damping Spring Elasticity: Reduced elasticity of the clutch torsional damping spring can cause the clutch to shudder when engaging. If it is confirmed that the issue lies with the torsional damping spring, the spring should be replaced promptly. Poor Contact of the Clutch Lining: Surface hardening of the clutch lining or the presence of adhesive substances can easily lead to clutch shuddering. Any foreign objects on the clutch lining should be promptly addressed. Uneven Elasticity of Pressure Springs: Uneven elasticity of the clutch pressure springs, inconsistent adjustment of the release levers, or an uneven end of the diaphragm spring release fingers can result in asynchronous pressure application timing, uneven force distribution on the pressure plate, and even tilting of the pressure plate. This leads to poor contact between the driving and driven plates, causing clutch shuddering. In such cases, it is advisable to visit a repair shop for inspection and replacement.
Having driven manual transmission cars for over a decade, if the car shakes in first gear during startup, it's mostly due to an uneven clutch pressure plate. When this component doesn't cooperate well with the clutch disc, it tends to slip and tremble during semi-engagement, especially noticeable on uphill sections. For older vehicles, it's also worth checking if the engine mounts have collapsed, as aged rubber can directly transmit engine vibrations into the cabin. Beginners often experience shaking from insufficient throttle or releasing the clutch too quickly - in such cases, applying more throttle while gradually releasing the pedal can make it much smoother. If shaking occurs only when the engine is warm but not when cold, there's an 80% chance the clutch disc has been contaminated with transmission fluid, requiring immediate leak inspection. Remember, prolonged driving with shaking is particularly damaging to the clutch trio (pressure plate, disc, and release bearing), and repairs can be painfully expensive.
