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 extremely difficult. Unauthorized modifications can lead to module current overload protection, resulting in a lock. In China, you need to use the factory online engineer account to reprogram it. It's basically impossible to perform online decoding overseas. We strongly warn against blind electrical modifications on modern integrated circuit vehicles.

We do not rely on the seller's verbal assurances. We provide multi-dimensional accident-free certification by cross-referencing insurance claims records, service orders from authorized dealerships, and conducting on-site paint thickness measurements and weld point inspections of the chassis and structural components (longitudinal beams, A/B/C pillars, shock absorber mounts).