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).

Most models adjust through the central control screen menu, while a few models (like some BYD or MG) retain physical levers or paddles on the center console or steering wheel. We will check if the drag feel when the system engages is linearly normal.

To ensure the legal rights of both parties, the "International Used Car Sales Contract" we signed is in both Chinese and English. Generally, the contract is governed by Chinese law. All liabilities for breach of contract and force majeure clauses will be clearly defined in the contract.