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).

The commercial invoice and export license we provide are based on the vehicle's underlying VIN and official Chinese nameplate data. If there are minor discrepancies with the destination country's customs system parameters (such as curb weight), we will issue a "Parameter Explanation Letter" stamped by our company to assist you in explaining, but we cannot change the official document data.

Europe and some developed countries have very strict regulations on greenhouse gases. If required by customs, we will specify the exact refrigerant type and charge amount according to the vehicle's air conditioning compressor nameplate in the remarks section of the packing list and commercial invoice.