A/C smells Cars affected: All Air Conditioning equipped cars. Symptom: A bad smell when the Air Conditioning is used, often smelling of rotting fish or stale urine. Problem and cure: The smell is due to the Air Conditioning Evaporator surface becoming contaminated with dust and debris. This eventually starts to smell if it becomes wet due the condensation from the Evaporator and cannot dry out. The main reason for the Evaporator not drying out is the drain hole becoming blocked. You can make sure the drain hole is clear by CAREFULLY using the blunt end of a knitting needle to clear the hole from the engine bay (see photo for the location of the drain hole on the Evo 6). Be very carefully when doing this as the Evaporator is near to the drain hole and can be easily punctured. If the problem persists then the Evaporator surface will need cleaning with mild detergent. Ideally you need physical access to the Evaporator for this but as it is sealed in the system in the factory then an access hole needs to be cut in the case to get to it. Alternatively you can try a different method. Put the fan on fresh air intake and spray some (mild) disinfectant into the air inlet in the bulkhead (rather than inside the car). Run the A/C for a long period, at least an hour, to make sure some water is produced to flush the disinfectant away down the drain. There is no guarantee that this will work but it is worth trying before having to cut open the case. If in doubt consult an A/C engineer. It is worth noting that the main reason for bad smells from the A/C is due to the use of toiletries evaporating off of peoples skin and collecting on the Evaporator surface. Car air fresheners are also another source for contamination.   Approximate cost of repair: N/A Back to question page