Bad smell from my 1995 Odyssey that I have been told smells like a mouse nest. Odyssey and Accord should have same vents. If outside air is selected or air conditioner is running, there is no smell. A Honda mechanic told me that it could come either from the cowl or ductwork behind the dash. Would it be possible to use either air pressure to blow the system out or vacuum to suck this material out? It should be possible to narrow down where the smell is coming from. Thanks.

 

the inlet of the air is right below the windshield wiper, most of the time you got abuch of leaf, spiders and mold growing in there.

not sure there's a filter(probably not, for 95's, unless you have a bimmer) for the a/c.

you can flush the ducting and see if it comes back, just spray some simple green or mold killing juice(those home use bath room cleaning stuff have mold killing agent in them), let it sit for 15 minute and then flush it out with a garden hose, just water down the little slot.

no, water will not shoot out into the interior so don't worry.

repeat if needed, you could do a mini flush every time you wash your car.

 

If the smell comes when it is set to recirc then the problem is not due to leaves or spiders or whatever in the air intake as the air is being pulled in under the glovebox. This is actually a very common problem caused by mold growing on your evaporator core as it creats condensation every time the ac cycles and it cools and warms. The cure is to buy a product used specifically for this problem...i use frigi fresh which i believe is dealer only, not sure...turn the vents on full blast with the recirc button off and spray the product into the fresh air intake below the windshield. The difference will be immediate and amazing.

 

Thanks for your help. I will try it. Your explanation makes sense because I remember this happened last summer then disappeared over the winter. Relief not to have to tear the dash off and still not fix the problem.