We mainly collaborate with professional organizations certified by China's national CMA (Certification of Inspection and Testing Institutions). If you need the highest level of international endorsement, we can arrange for independent inspection agencies like SGS or TÜV to conduct Pre-Shipment Inspections (PSI) before loading at the port.

The technician will start the vehicle and turn on the air conditioning system, measuring the actual temperature at the vents at the lowest and highest settings with a thermometer; at the same time, they will connect a manifold pressure gauge to check if the refrigerant pressure in the high and low pressure lines is within the normal range, determining if there is a chronic refrigerant leak.

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).