I recently bought a used 2008 Element. The prior and only owner had a dog. The inside smells slightly doggy but when I use the air vents in any mode the smell is really doggy. Can anyone suggest a solution? I have tried the obvious things.
There may be mold or mildew in the ventilation system. Have you tried the obvious thing of spraying some odorant into the intake vents in front of the windshield when you have the AC/Heat fan on high and NOT recirculate? I’ve used Lysol and small amounts of Clorox cleanup before. Be very careful not to over use the bleach product lest it get onto your carpet and upholstery with bad results. It will kill the mold though. Maybe Febreeze is worth a shot. Leaving the windows open on several sunny days will also help.
Or you could consider changing your handle to Smelly Elly.
I would spray some Ozium through the system.
Ozium is very good at covering up unpleasant odors, which is why it is the air deodorizer of choice in mortuaries. However, I would suggest first using a regimen of Lysol spray in order to kill likely mold and its spores. If the odor is really bad, I would do the Lysol treatment a few times, on alternating days.
Then, after using Lysol to kill whatever might be growing in those HVAC passages, Ozium would be good for getting rid of residual odors.
Change the cabin air filters .
What MG McAnick and VDCdriver said. With the engine idling, turn on the fan, turn the heater control to halfway between hot and cold, and spray a can of Lysol into the vents on the OUTside of the car at the base of the windshield.
You might want to visit a good detail shop in your area. They will go over the entire interior of the vehicle and they are very good at removing odors. I use them whenever I buy a used vehicle and they are worth every penny of what they charge.