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).

It's not mandatory. Four-wheel alignment and dynamic balance are part of routine maintenance. During long-distance towing and sea transport, the suspension may experience slight changes in stress. We recommend that buyers perform a four-wheel alignment locally after picking up the vehicle at the destination port and replacing tires suitable for local road conditions.

We will use a megohmmeter (insulation resistance tester) to measure the insulation resistance of the high-voltage bus. If the resistance value is below the national safety standard, it indicates a risk of leakage, and the vehicle will be deemed unqualified.