We use two steps: 1. Insert a medical-grade endoscope through the spark plug hole to visually inspect cylinder wall scratches and carbon buildup on the piston top; 2. Extract an engine oil sample to check for large metal debris or emulsification (caused by coolant leakage).

Our standard holding period is 3 business days after the deposit is paid (based on the timestamp of the payment slip). The domestic used car market in China moves very quickly, and if we do not receive the bank message confirming the deposit within the specified time, the system will automatically release the hold, and the vehicle will be re-listed for public sale.

The technician will put the vehicle in neutral on the lift, rotate the wheels, and listen for any abnormal metal gear whine from inside the motor reducer, and check for gear oil leaks at the joints of the reducer housing.