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.

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 not. The U.S. DOT and EPA have strict import restrictions on non-compliant vehicles. Any Chinese used car that is not 25 years old and not produced to U.S. standards will face mandatory crushing and destruction upon arrival at U.S. ports. We directly reject such non-compliant orders.