What is the issue when a car doesn't move after shifting gears?

[McHarmony]

When a car doesn't move after shifting gears, it is a comprehensive functional failure involving the clutch, transmission, and drive axle. Below are relevant explanations about car starting: 1. Reasons for difficult cold starts: Poor fuel quality often results in low volatility of inferior fuel, especially during winter when temperatures are low. During a cold start, the engine block temperature is low, making it difficult for the fuel to atomize. This leads to insufficient mixing of fuel and air in the cylinder, causing starting difficulties or even failure to start. The lower the temperature, the more fuel is required for a cold start, and the presence of carbon deposits will significantly affect whether the cold start proceeds smoothly. Carbon deposits in various parts of the engine negatively impact its normal operation. 2. Solutions: Replace the fuel pump, adjust the valve clearance, inspect and promptly replace the coolant temperature sensor, and replace the relay.