This Q7 came to us after sitting for a stretch of Vancouver’s wet season. The owner opened the door to find mold across the seats, door cards, steering wheel and dash. It looked bad, and it smelled worse. Growth this widespread almost always means water is getting in somewhere, so the job was as much about finding the source as cleaning the interior.
Killing the mold first
Before anyone works inside a vehicle like this, the mold has to be dead. We started outside: a full exterior detail and clay bar decontamination so we weren’t sealing a dirty shell around a treated cabin. Then we fumigated the interior with chlorine dioxide, which reaches the spots a wipe-down never will, and aired the vehicle out.
Finding the water
With the interior safe to work in, we pulled the seats and lifted the carpet to check for trapped moisture. There was buildup under the driver’s side seat base foam, exactly the kind of damp pocket that keeps feeding mold after a surface clean. Tracing it back, we found a leaking sunroof drain that had been quietly emptying into the floorboard. We cleared the drain and confirmed it was flowing properly, because none of the cleaning matters if the water keeps coming.
The deep clean
Once the cabin was dried out, we did a full interior mold detail: enzyme cleaner and steam on the affected surfaces, plus an extractor on the fabrics and carpet liner to pull contamination out instead of pushing it around. The AC system got attention too. We refreshed the vents and evaporator side and cleared a blocked AC drain, another moisture source waiting to restart the problem.
Finishing up
We ran an ozone generator as a final treatment, conditioned the leather and trim, and let the interior dry over the course of a day. The Q7 left dry, clean and without the musty smell, and with both of its water problems fixed rather than perfumed over.
The lesson from this one: mold across an interior is a symptom. This vehicle had two separate drainage faults, and treating the visible growth without fixing them would have meant doing it all again in a month.
