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 inspection report only represents the physical condition of the vehicle at the moment the inspection was completed (down to the minute). Once the vehicle begins long-distance inland towing or international shipping, the report no longer guarantees the future condition due to drastic environmental changes.
Obtaining precise internal resistance at different SOC levels requires disassembling the battery pack and connecting it to a professional charge-discharge cabinet for several days of cycling tests. This is beyond the scope of non-destructive used car inspections; we only provide real-time estimated internal resistance data based on OBD port readings.
