Request a live video call during the test drive rather than a pre-recorded one. Cold start first: listen for rattling or metal scraping in the first seconds — possible timing chain or hydraulic lifter issues. During acceleration, a whining from the gearbox area can mean bearing wear; hesitation or jerking in an automatic suggests transmission problems. Braking: the pedal should feel firm, not spongy, and the car must not pull to one side. Turn the wheel fully in both directions and listen for clicking — a classic CV joint fault. Insist on a highway segment too: vibrations above 100 km/h often point to unbalanced wheels or bent rims. Ask the driver to film the dashboard throughout — warning lights that flicker on briefly are still faults that OBD will record.

This involves personal privacy, and we have no right or ability to retrieve personal driving violation records from the traffic police system. We can only infer if there was aggressive driving by checking if the engine has been reprogrammed with a higher-level ECU (stage 1/2) or if the transmission has a history of severe overheating.

It's extremely difficult. Unauthorized modifications can lead to module current overload protection, resulting in a lock. In China, you need to use the factory online engineer account to reprogram it. It's basically impossible to perform online decoding overseas. We strongly warn against blindly modifying the electrical systems of modern integrated circuit vehicles.