I had same problem and a mechanic friend changed the filters in air con system - all's well now.
K
August 2009
The smell is from bacteria that has formed on the surfaces of the evaporator inside the car. You can buy aerosol treatments for this - generally you open a can of this stuff, set the control for interior circulation, let the contents of the can circulate for a while and the smell should go, or at least diminish. Check out Halfords or any good motor factors.
John
April 2009
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