Cabin air smells bad when AC unit is on.1994 Dodge Caravan

1994 Mercury Capri ac does not have a cabin air filter. Weak air flow and bad smell could be debris in the fresh air/ac inputs. Check under the hood for debris where the air enters, the area under the wiper, and behind the vents inside, they get clogged if you park under a shedding tree...Chris

Mildew smell? If so try blowing out evaporator drain tube under vehicle. Check and if not clogged get more information and will try to help.

I've had Caravans for many years and never had that problem however, if there is a cabin filter in the vehicle it is inside the air exchange box and you will have to open it to find the filter. Most likely in the top.

You need a cleaner such as this:

http://www.autogeek.net/1z-einszett-klima-cleaner-air-freshener.html

You may be able to find it at your local auto parts store.

On the 2005 Dodge Grand Caravan the interior AC filter is located under the dash on the passenger side. You need to slide the cover forward and then pull down. The filter is longer than the distance between the floor and the unit, but it bends. Ensure when you replace it you only bend the amount you need to install or you could damage the filter and to seal between the housing and the filter.

the smell you have, does it smell like antifreeze? if so, you need to replace heater core

On the passenger side somewhere below the glove compartment, you should see a bracket that you will need to slide out towards the seat and then pull it off. The filter is located behind this.

Then you don't have one.

Does your van have a cabin air filter?? Check door on passenger side floor board to make sure it closes. May be vacuum problem

I HAD THE SAME PROB WITH MINE I REPLACED THE HEATER CONTROL PANEL & IT FIXED IT