Q: Bad smell in AC vent

asked by on October 13, 2016

I have a bad smell coming from the AC vent every time I turn on the AC. I have already changed the cabin filter and tried the Lysol method. Is there anything else I can do to get rid of this smell?

My car has 72000 miles.
My car has an automatic transmission.

Hi there. This is a concern I have had a lot of experience with. Has the AC drain grommet been updated or removed? The original grommet was designed with a small slit style opening and was found to not be sufficient in draining moisture from the evaporator. There would be a build up of mildew that prevented proper drainage thus resulting in Lexus authorizing the removal/replacement of those grommets under a limited bulletin.

If the grommet is not the issue, then moisture buildup inside the evaporator case is the issue. Toyota Motor Company released a tech tip to the dealerships that describes how to reduce the smell and I’ll give you the short version here: during the last 5 to 10 minutes of your drive set the climate control to max fan, fresh air, max cold, no AC, and leave the fresh air setting on when shutting off the vehicle.

This setting allows mass amounts of fresh air to dry the evaporator and case to the point where mold and mildew cannot thrive and leaving the fresh air setting on will allow the evaporator case to breathe and dry out. You may have to do this several times to help with the smell or an AC refresh service available at most service centers may be necessary if the smell is pretty substantial right now. Once the smell is gone, you may only need to do the tech tip once in a while as long as you make sure the fresh air setting is on when you turn off the vehicle. Your mechanic has several technicians available to inspect the air conditioner system and move forward with repairs.

Was this answer helpful?
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・Fair and transparent pricing

Get a quote

What others are asking

The car has no electrical power at all

Hi. I would recommend to have a technician check for any loose power or ground wiring. There also could be some corrosion present that is blocking the electrical current flow. I also recommend that the technician use a test light to...

Thermostat problems

There are a few common causes for the AC blowing hot air, the most common is that the vehicle is low on refrigerant, other causes could be the blend motor has failed or the compressor is not working properly. A...

Flat tire won't hold air

Radial tires usually will hold some kind of air as long as the object that caused the puncture is left in the tire. If removed then yes, the tire will most certainly go flat right away. Radial tires can usually...

Related articles

Why Won't My AC Blow Cold Air?
When you turn on the air conditioner in your car, you expect to receive a flow of fresh, cold air....
Do All A/C Systems Use Refrigerant?
All air conditioning systems use refrigerant. Refrigerant dissipates heat in the air conditioning system to keep your car cool in hot weather.
How Long Does an AC Clutch Cycling Switch Last?
An An AC clutch cycling switch is the part of your car’s air conditioning system that engages and disengages with every cycle of your air conditioning compressor. Realistically, you probably don’t use your air conditioning every single day, unless you...