mold/mildew smell when starting up the AC?

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

concretejungle

concretejungle

10 Year 15 Year 20 Year
Joined
Oct 27, 2003
Threads
490
Messages
9,916
Location
North Cadillac
Like the title says, anyone else noticing this problem? When i start the truck up after sitting in the lot or at home and the AC turns on, i get a minute of stinky air as if there is wetness sitting in the system.

Anyone else experiencing this?
 
Did you check the ac filter if it was dirty? Also there are some sprays that ac specialists use to clean out the ducts if I'm not mistaken
 
I've had this happen in a variety of cars but never figured out how to prevent it.

I've tried turning off the A/C (but leave the fan blowing) for a little bit before getting out of the car. My attempt to decrease condensation on the evaporator, but probably does nothing.
 
I had this problem with both my Mercs and it was caused from not running the A.C often enough. The smell went away after regular use. It happens from not using the A.C during winter. Now I just use the A.C a little more often in the winter which really helps prevent your window from fogging up as well vs. using your engines heat.
 
hmmmm... my truck is pretty new, just turned 10,000 miles over the weekend. This is the first "summer" that it's even ran the AC....
 
Random but I hit 10K this weekend as well. And I have the same issue with mine. I had a Rover from 0 to 15K and it smelled amazing, my cruiser not so much. I guess I'll change the air filter this weekend.
 
The only time I ever smell that in vehicles is when I STOP running the AC and just blow uncooled air. Like others here, I'm not sure how to stop it, but I also don't think it's unique to the LC.
 
This was a major problem in my wife's Toyota matrix a few years ago. We (I) would go out in the heat and run the heater for 5 to 10 minutes to dry out the heat exchanger. Once everything dried out there was no more smell for about a month. Then I'd go out an dry it again. I think that there are sprays available to keep stuff from growing on the condenser fins. We sold the car before I got around to getting the spray.
 
It's bacteria build up in and around the evaporator. You can buy disinfectant foam sprays with a long pipe to get down into the vents, you will also need to get in to the evaporator housing with it as well, there is normally a evaporator sensor that can be removed that allows you to get in there.
 
My '14 Land Cruiser A.C has never had any smell. Maybe you guys live in a more humid climate? Try the replacing with a better aftermarket filter like others have mentioned
 
It's funny that this thread popped up because I just got back from the dealer for this very issue. I have a 2016 with just over 7K miles, the smell started about 3 weeks ago and it's only noticeable when I start the vehicle up after it has been sitting for several hours. It is a very noticeable smell however, and it's very unpleasant. The dealer told me I need to keep it on fresh air intake more often to prevent the buildup of moisture in the evaporator, which I doubt is true. But they did do what they called an "A/C refresh" and sprayed some anti-mildew stuff into the evaporator and cleaned it. I don't know if this will fix the problem, but we will see.
 
bigbassinbob said:
It's funny that this thread popped up because I just got back from the dealer for this very issue. I have a 2016 with just over 7K miles, the smell started about 3 weeks ago and it's only noticeable when I start the vehicle up after it has been sitting for several hours. It is a very noticeable smell however, and it's very unpleasant. The dealer told me I need to keep it on fresh air intake more often to prevent the buildup of moisture in the evaporator, which I doubt is true. But they did do what they called an "A/C refresh" and sprayed some anti-mildew stuff into the evaporator and cleaned it. I don't know if this will fix the problem, but we will see.
Click to expand...

I believe they are correct. My Merc. dealer said the same thing and it cleared up that smell in both my cars.
 
They did it under warranty since an $85k vehicle shouldn't have the a/c smell like mildew within the first year.
 
bigbassinbob said:
They did it under warranty since an $85k vehicle shouldn't have the a/c smell like mildew within the first year.
Click to expand...

On the other hand... Air and moisture have similar tendencies whether it's an $85k or a $30k. ;) I dunno... Maybe we have a resident expert who can shine the light on this.

My brand new Subaru WRX used to get that smell if I turn the AC compressor OFF... So does my wife's Outback.
I haven't noticed it on my 200, but definitely on my 100.
 
This happens in a/c systems fitted into buildings as well, it is often called Dirty Sock Syndrome. There has been arguments as to whether the bacteria/mildew present is bad for your health. I worked in a dealership and we used to advise to get it disinfected annually.
 
What doesn't make sense to me is why fresh air intake would "dry out" the air as opposed to recirculated air intake. The air outside is much, much more humid than the air inside. Also, I've never had this problem on any vehicle in the past - Range Rover, LR4, Honda, 4Runner. It's not like I'm doing anything differently with my a/c habits than I've done in the past.

My point, Markuson, was not that I think air behaves differently in different vehicles. It's that this is the Toyota flagship vehicle that I purchased less than a year ago. Unless Toyota designed Land Cruisers to smell like mildew within a year, the problem should be fixed under warranty.
 
You must log in or register to reply here.

Share this page

Back
Top Bottom