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).

Absolutely prohibited. Chinese customs requires a "bare car" declaration for used car exports. If undeclared goods are found inside the vehicle, it could lead to inspection and detention, or even smuggling charges. We refuse any form of concealment requests.

Currently, in most developing countries, there is a severe lack of deep repair capabilities for the three electric systems. We recommend that B2B car dealers must have basic electrical insulation testing capabilities.