The technician will start the vehicle and turn on the air conditioning system, measuring the actual temperature at the vents at the lowest and highest settings with a thermometer; at the same time, they will connect a manifold pressure gauge to check if the refrigerant pressure in the high and low pressure lines is within the normal range, determining if there is a chronic refrigerant leak.

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.

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.