Musty AC?
 

Hi all, I'm considering purchasing a 2016 ILX, tech package with a-spec. Currently I'm driving a 2013 Lexus IS 250 F-Sport (with 15k miles on it) that I got back in November. Unfortunately, since it got hot here in North Carolina the AC in my Lexus has started smelly musty, like mildew/mold, when I first turn on the car. The smell goes away after about a minute, but I know the cause of the smell is still present.

I've had it at the dealer twice and they've "cleaned" it both times, at no charge, but it doesn't last and the smell comes back 1 - 2 weeks later. Based on my research this is a very common issue with Lexus cars. Most owners seem to just deal with it, which I find completely unacceptable for a car this expensive. I can't stand the smell so I'm thinking of trading in the IS and getting an ILX (and eating the $7k it's going to cost me). I'm not confident that there's an actual solution to the problem and the thought that there's mold/mildew growing in the ventilation system doesn't jive with me.

Prior to the Lexus I was a Honda guy. I've had a 1996, 2005, and 2006 Honda Accord. My wife drives a 2009 Honda Odyssey. None of these cars ever had smelly air conditioning. Not once. Ever. I know the ILX has been out since 2012 and that some of you here have quite a few miles on them. So, my question is, does anyone here have any problem with musty air coming from the AC?

Although I live in Northern California which has had a lot of 100+ degree days so far, I haven't noticed any problem. Of course we don't have the humidity problems that you have.

I've had my 2016 for a week and a half now and have used the AC quite a bit and I have no scent issues.

Is there a cabin air filter to replace on the Lexus? I understand you have taken it to the dealership and they have "cleaned" something, but you can always try to pull the filter yourself and take a look at it.

Yah, the cabin filter was the first thing I changed. It didn't improve the situation, unfortunately. I've tried just about every remedy I can think of, none of it lasts long term. Personally I wish it would because I really like the car, but I can't keep it with this issue.

Don't know what the dealer is doing to address your issue or what they're doing to clean it, but it seems like you have mold and bacteria on the evaporator core.

Before getting rid of the car, I'd try cleaning it yourself. Many products available to get rid of (not mask) the odor and odor-causing mold like....

- 1Z Einszett Klima-Cleaner: 1Z Einszett Klima-Cleaner Air Conditioner Treatment ;
- Interdynamics 760 Auto Air Conditioner A/C and Heater Duct Cleaner:

- Lubegard 96030 Kool-It Evaporator and Heater Foam Cleaner:

Toyota also makes a kit:


To really get at the source, it's best to shoot the cleaner up into the drain tube under the car vs through the center vents. Here are a few DIY tutorials showing the process...

DIY: A/C Odor Cleaning - Toyota Nation Forum : Toyota Car and Truck Forums





The problem comes down to you not letting the moisture evaporate fully from the evaporator. Mold builds up from the left over moisture and you get that stinky smell. Once you get it cleaned up, in the future when using your A/C, just turn off the A/C itself but let the blower fan run for a minute or 2 to help get rid of excess moisture and dry out the evaporator.

This reminds me... I need to do this to my dad's car (Toyota). I've never had this issue with my car. But I also shut off the A/C and just run the blower for 1 minute before I get to my destination and park the car.

Thanks for the tips. Unfortunately, I'm aware of the Toyota cleaner, but its not easy to use on the IS250. The AC drain hole is located directly above the transmission and is not easily (or at all, really) accessible without dropping the tranny. You can't actually even seen the drain when looking under the car. It's terrible placement, if you ask me. Otherwise I would have already done that.

Turning off the AC before I arrive at my destination is something I've seen numerous times before. To me, that's ludicrous for a car as expensive as an Acura or a Lexus. It has automatic climate control, I use it because its automatic, not because I want to fiddle with it to overcome what's clearly a design flaw. I never, not once, did that with my Accord and never had an issue.

Maybe its just me being used to musty-smelling mid 90's Honda systems.

I've always taken a proactive approach to it and run the vent system w/o the AC on for the last 3-5 min before I park. It helps dry everything out so you don't leave any condensation in the system for a long time after you park.