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.

For older vehicles or those used in high temperature and humidity areas, we will focus on opening the hood to check if the insulation of the wiring harness in the high-temperature area of the engine compartment is cracked or brittle, to identify potential short circuit risks that could lead to spontaneous combustion.

We maintain an absolute skeptical attitude. In addition to regular visual inspections, we focus on checking for sediment accumulation around the sunroof drainage channels and look for water stains under the A-pillar trim and front floor mats. This is the only effective physical evidence to determine if the sunroof drainage holes are blocked, leading to hidden leaks.