4S dealership records are directly connected to the manufacturer's database, making the data hard to tamper with and the most reliable, with original parts guaranteed; third-party repair shops usually are not connected, making their data unverifiable. Therefore, we only consider the connected records from 4S dealerships as valid historical documentation.

During the stationary steering test, the technician will check the smoothness of the steering wheel from full left to full right, looking for any unusual noises from the steering gear; they will also inspect the hydraulic power steering pump (if present) and the seals of the steering column for any hydraulic fluid leakage.

Experience turbo lag and power surge during road tests; check for significant oil accumulation at the turbo intake and intercooler connections (slight oil vapor is normal); and use OBD to read the real-time boost pressure peak to see if it meets factory settings.