How can we get rid of a foul smell in our 2005 Kia Sedona that comes and goes?

If it comes and goes while the air conditioner or heater are working, and has an amonia smell to it, a mouse may have gotten into the external vents. Youwill need to remove the outer cover and clear out the nest.

If it is the result of mold or mildew from the inside and seems to come out when the car has been sitting for a while, especially in the sun, you will need to shampoo the carpet and upholstery using a detergent with fungicide (do yourself a favor and have the interior detailed instead).

If it is a sour smell due to something being spilled inside or in the trunk, again shampoo or detail the interior.

In all cases, after you have had the problem area cleaned, spray the interior with a full bottle of Masengil Douche product. It may sound strange, but it works, and only this brand will work well. In the event of the mouse, pour a portion in the external vents, a little each day, and spray it into the interior vents without the fan running, a little each day.