Skip the auto shop - Our mechanics make house calls

Q: Sour, stale smell coming from air vents

asked by on

Sudden onset of of sour, stale smell coming from air vents. Car has always been in garage but stayed outside for 10days. Now has odor coming from air vents. Almost smells like cat urine when car first gets going then turns into a really stale mothball smell. Any product I can use to elongate this smell

My car has 99000 miles.
My car has an automatic transmission.

A: This is most likely a cabin filter that nee...

This is most likely a cabin filter that needs to be changed. Your car is equipped with an air filtration system that works similarly to your engine's air filter in that it filters the outside air as it flows into the cabin of the car when you have the vents open. Over time this filter will get dirty just as your engine air filter does and, in some cases as you describe, it will emit an odor or smell that is filtered into the cabin when you turn on the vent air.

I would recommend having an expert mechanic, such as one from YourMechanic, come to your location to replace the cabin air filter for you.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: 2009 Toyota Sienna, runs fine, fluids full, no heat inside vehicle, causes?

Hi there. It sounds like the air mix servo for the temperature control may have failed. These models were also prone to radiator and water pump leaks. The leaks would be slow and not produce fluid on the ground; sometimes...

Q: Engine rod knock

Hello and thank you for contacting YourMechanic. The oil to use is a thick 15/40W oil for diesels. This oil is thicker than normal engine oil and can keep an engine from knocking for a little while. If the engine...

Q: Mice can get into the ventilation

Rodents can become a serious problem for almost any vehicle. If they don’t find their way into the HVAC system, they will often chew on wires, which can cause serious problems with vehicle operations. In this case, cutting and installing...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...