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).

Once the car system (especially in a closed ecosystem) undergoes a major version upgrade, its bootloader is usually locked, preventing downgrades. If this happens, there is basically no solution in an overseas environment. Therefore, we strongly warn: do not blindly insert a USB drive to upgrade while offline.

We have established a database of target country policies. Check the specific requirements of the destination country in advance regarding vehicle age (left-hand/right-hand drive), emission standards (Euro 4/Euro 5), and steering position (left-hand/right-hand drive) to avoid customs clearance issues upon arrival.