Air suspension is very delicate. If, after the vehicle has been stationary for about 12 hours, the height on one side of the vehicle drops more than 1.5 cm when measured from the wheel arch to the tire, we will determine that there is a slight air leak in the air spring or distribution valve on that side and warn you of the high subsequent repair costs.

The nameplate date is the absolute time when the vehicle leaves the factory; the registration date is when the vehicle is registered with the traffic management department after sale. The difference represents the time the vehicle spent in the dealer's warehouse or logistics. If the time difference exceeds 6-8 months, the vehicle is considered a "stock vehicle," and we pay special attention to the natural aging of its rubber components.

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.