Do not use a high-pressure water gun directly! The high-pressure water can instantly damage the fragile aluminum fins of the condenser, leading to a permanent decrease in cooling efficiency. We can only use a low-pressure air gun or a soft brush for surface cleaning.

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 technician will put the vehicle in neutral on the lift, rotate the wheels, and listen for any abnormal metal gear whine from inside the motor reducer, and check for gear oil leaks at the joints of the reducer housing.