How do I clean my car's air conditioning system?

I recall that you gave advice some time ago regarding 'fumigating' the air conditioning and ventilation system to get rid of noxious smells. I've tried to locate this in your FAQ's and forums with only partial success. Please can you repeat the detailed advice, which I recall involves a spray and running the systems with no one in the car?

Asked on 5 September 2010 by johnnyb686

Answered by Honest John
Get a can of Autoglym Air-Con Sanitizer (RRP £11.99) and follow the instructions. It requires leaving the car running with the vent switched to recirculate for 15 minutes, while you stand outside and watch.
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