Can I Spray My Cabin Air Filter? – Yes, but don’t make this error


I’m a mechanic and I drive a ton of different cars every day, a bad-smelling car is a common problem. It’s not the customer’s fault, some car maintenance jobs are neglected by the professionals and the cabin filter is at the top of that list.

Cabin filters may be sprayed with air fresheners. However, avoid adding an oil-based freshener, as they will block filter airflow.

In this post, you’ll learn what not to spray on your cabin filter, you’ll learn my hack for super fresh car interior for weeks on end and you’ll also learn why some cars smell bad

Spraying Cabin Filter

You can spray your cabin filter, choose your favorite fragrance and simply spray the filter, Walla! A sweet-smelling ride. But just before you start spraying let’s just check what you’re using. You’ll need to avoid essential oils and the like, they will serve to block the filter and that’s bad for the heater and cabin comfort. If air can’t pass through the filter, it can’t dry, cool, or heat the cabin air.

Using a regular dry spray air freshener like Febreze is perfectly fine. Remove the cabin filter vacuum the filter to remove any dust, leaves bugs, etc., and give it a coat of your favorite freshener, pop it back in and enjoy.

You should note, the fresh smell doesn’t typically last too long, a few days, and the usual odor is restored. So if you want an odor to last a few weeks, check out the air freshener hack below.

Adding Car Freshener To Cabin Filter

Cabin filter and air freshener

Ok, so you want your freshener to last a few weeks rather than days? stupid question, who wouldn’t. Here’s a hack I’ve been using for years. I didn’t invent it and I can’t remember where I learned it, anyway, credit to whoever passed it to me, I’m now passing it on.

For a fresh smell that last weeks or more follow these simple steps:

  • Remove the cabin filter
  • Clean by vacuuming or better, use a new one
  • Buy your favorite air freshener, buy a good quality brand name
Cut air freshner
  • Cut the freshener into strips narrow enough to slip into the pleats of the filter
Check cabin filter airflow
  • Replace the filter, be sure to fit the filter correctly (note the arrow on the filter)

That’s it, a simple easy solution to a stinky cabin, Enjoy!

Where Is My Cabin Filter?

Cabin filter in glovebox

Finding the cabin filter, always a great game, all the techs in our shop play it every day when a new model arrives. Sure we could look it up, but we are supposed to be pros.

Finding them can be a challenge, even for the pros. Anyway here is a list of the usual spots they hide them:

  • Behind the glovebox
  • In the foot well
  • In the air intake under the hood
  • In air intake in the windshield cowl (exterior)
  • Battery cover integrated
Cabin filter in footwell

How To Remove Cabin Filter?

First step – locating said cabin filter cover. If you can’t find it within about 1 minute, go ahead and look it up, some models really do go above and beyond.

Cabin filter removal

Most will fit them behind the glove box. A plastic arm on the glove box is normally easily manipulated in order to allow the box to open wide – a service mode if you like. Now that said, you’ll need to be careful here, some glove box arms are delicate and there may be a clip to be removed. If in doubt google or YouTube.

Found it? great! Follow these steps to swap it out:

  • Press the release tabs on the cabin filter cover or remove fasteners
  • Remove the filter and discard
  • Refit new filter, but be mindful of the directional arrow on the filter
  • Refit the cover

That’s it, not rocket science.

Why Some Cars Smell Bad

Sammy
Luv u Sammy

Some cars really stink, and the reasons vary. Some are obvious, wet dog, old sneakers, half chicken nugget wedged in the seat rail, you know….life.

Other reasons are of course less obvious and they’re the ones I list here.

  • Bacteria covered cabin filter
  • Rodent infestation
  • Bacteria contaminated a/c evaporator
  • Evaporator gas leak
  • Exhaust fumes entering the cabin
  • Water leak in cabin area
  • Heater core coolant leaking into the cabin
  • Car interior plastics gassing

Without a doubt, a weekly vacuum and interior wipe-down will improve how a car smells. When dust builds up inside your car it becomes airborne and gets into areas you can’t ever get a vacuum cleaner. When that dust (skin cells) becomes damp and starts to decay, it causes a stink.

What Happens If I don’t Change The Cabin Filter?

Dirty cabin filter

Cabin filters are important, sure they filter leaves and bugs. But I’ve found a lot worse in there – mice, rats, and dead birds. Inhaling bacteria will have some harmful effects, especially if you’re prone to allergies.

Replacing your cabin filter once a year before the summer season with a top-quality filter will remove particles as small as two microns. That means you and your family aren’t exposed to pollen and silica dust and bacteria-laden air.

Running an HVAC system with a dirty bacteria-laden cabin filter may cause:

  • Respiratory issues
  • Heating system strain
  • Air conditioner evaporator bacteria contaminated

Treat yourself to a new filter, you’re worth it!

John Cunningham

John Cunningham is an Automotive Technician and writer on Rustyautos.com. I've been a mechanic for over twenty-five years, and I've worked for GM, Volvo, Volkswagen, Landrover, and Jaguar dealerships. My passion is cars. I use my knowledge and experience to write articles that help fellow gear-heads with all aspects of car ownership, including buying advice, maintenance, and troubleshooting.

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