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).

Under FOB or CIF terms, all risks before crossing the ship's rail are borne by the seller (us). For minor scratches, we will provide a price discount based on the damage assessment; for serious damage, we will immediately terminate the vehicle delivery, refund the full amount, or replace it with a vehicle of equivalent configuration.

All our measuring instruments (especially calipers, paint thickness gauges, and refrigerant pressure gauges) are calibrated quarterly according to ISO quality management system requirements to ensure the data we provide you is objective, accurate, and reliable.