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).

After receiving the final payment, we will send you the complete set of original customs clearance documents via DHL or FedEx, which typically includes: - Bill of Lading (B/L) - Commercial Invoice - Packing List - Certificate of Origin (CO) - Used Vehicle Export License issued by the Ministry of Commerce of China Note: If your local customs requires additional documents (such as VIN consistency certificate), please inform us in advance before shipping.

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.