I have a 1999 Mazda Miata and last year the mice made their home in it…the smell is outrageous…I have tried everything and can’t get rid of the smell! As soon as I start to drive, the odor permeates the car and it is sickening! Help!
Remove the carpet and completly clean everything with a solution of bleach and water let dry (air OUt) then have the carpet replace. Hope this helps. P.S. make sure to use a face mask!!!
Time heals all wounds, and smells, unless you have cloth seats. I’m guessing that you are smelling the residue from mouse urine, right?
There are an array of enzyme based deodorizers out there that might help, if you can find and get to the spot where they relieved themselves.
I successfully removed the smell of years of cigars from a car via a method similar to what the other poster on this thread suggested. Carpet and seats came out. Covers came off seats, and everything got cleaned and put back in.
Good luck.
ozone generator
you may have a rodent problem, nesting in the air box somewhere, with the attendant urine feces smell.
take it to an AC radiator place. they can troubleshoot it for you. and save you the aggravation.
the animal may have crawled up into the air intake duct.
when you turn ON the AC the blend door shuts (thus shutting off the outside air coming into the car) so the only air you get is what is inside the car. when the blend door is open, you get a mix of fresh (stinky) and recirculated air.
as an aside, if you use the recirc button does that change the smell? the recirc button is the one with the round and round arrow on it. lit is on recirc, and unlit is not recirc.
you may still have the mouse nest (with the unine and feces) inside the ducting from the engine compartment to the heater under the dash.
all the special chemicals and cleaning won’t really help if there is still a nest and the detritus from it still in the duct.
How does one know what a mouse smells like unless they have picked one up to smell it?? 
i’m assuming like my sneakers!
something no one wants near them, and people breath easier when they aren’t around.