My 2003 Elantra GLS recently developed an unpleasant smell in the cabin. I narrowed it down to the air conditioner (didn't seem to have anything to do with the fresh air vents). I washed out the engine compartment, made sure the drains where the windshield meets the hood were clear and checked to see if there was an air filter behind the glove box (in the fax compartment) that needed replacing (there wasn't a filter installed). The smell has been reduced, but I never found anything so I don't know what caused it and more importantly if there is somewhere else I should be looking - any ideas?