Ok, its been 3 months since new, and im smelling what "wwest" or some other guy that posted about this strange AC humidity smell or whatever its causing this. Because of the heat recently, i use my AC now everyday, as opposed to the open windows method when i first got the car. But in this last couple weeks or so, im experiencing this odor that is kind of bad.

My passengers have noticed it for months but i always thought is the new car smell. My cousin says my car smells like *****, but hey! i only did it a couple times in the car so far, so i dont think it should be that. But it really smells kind of like THERE!! The smell is getting more noticable to me now, everytime i get in the car, i smell those strange mildew or wet leather odor which doesn not neccessary stink but its by no means a pleasant one. My girl even suggests an air refresher or one of those car perfumes. I hate those things so i refuse it even as a gift.

Are you guys experiencing this and what can i do to get rid of it?? Thanks guys.

Edit: Toned-Down Language

 

Yours sounds extreme and you don't say what area of the country, or the world, but since you state that you have been using the A/C I think I can assume HOT & obviously humid.

First, be absolutely sure the A/C condensate drain is completely open and free for the condensate flow. You dealer should be willing to check this out. Secondarily I would replace the A/C air filter just as a precaution.

Otherwise open the sunroof and windows and leave them open as often as you can.

There are two aftermarket devices that can help, one is a UV light with a small fan (Biozone 50V, 888-284-8044) about the size of two cigarette packs, and the other is at:

http://www.airsept.com/eed.html

Good luck.

 

Yeah I would definitely check the A/C drain to make sure collecting water is being released from the car. If that gets plugged up, then over time it will actually turn into icy slush inside the vent and you can hear it when you go around turns.

But the smell is probably an extreme example of the buildup of mildew inside the A/C system. Running the A/C very cold and then turning it off creates a lot of condensation in the system, which combined with the heat of the outside weather, allows mildew to grow.

It's pretty raunchy in some cars, maybe due to the type of plastic used in the system, or other chemicals, I don't know. I have observed that the bad smell seems to be much worse in systems using the new refrigerant, vs. the older freon systems.

One way to control this problem is to allow the vent to run with the fan on full blast with the A/C turned OFF for a couple of minutes before turning off the ignition. Helps to bleed out the condensate.

Another way is to disinfect the vent ductwork. I saw another thread on clublexus that described spraying lysol into the bottom edge of the vent intake on the outside of the windshield housing, then blowing air through the system for a few minutes. Lather, rinse, repeat.

Ral

 

The bad smell is worse, and more prevalent, in cars with the new refrigerant. The new refrigerant is much less efficient and that meant the manufacturers had to overcome that {loss of}efficiency by making the cooling evaporator much more efficient.

10,000 sq inches of surface area vs 3 to 4000, makes it act much more like a sponge, holding a thin film of condensate for many hours on end, a perfect breeding environment for mold and mildew spores.

In a typical US climate it can take more than an hour for the liquid refrigerant reservoir to be emptied and then for the evaporator, previosuly kept at 35F, to rise to the point at which this thin film will begin to evaporate.

The environment:

1. Dark
2. warm (warms to above 55F overnight)
3. Food (all of the atmospheric "debris" carried by the incoming airflow)
4. huge surface area for plentiful growth.

I was recently told by a Porsche Factory representative that the primary reason most manufacturers run the A/C compressor far below the temperature wherein it is useful for human comfort, 55F, is to provide a condensed film of moisture for covering the virtually indestructable bacterial spores and thus preventing the odor of their "leavings" from permeating the cabin.

So you only detect the odor at first, when you first start up, and then the evaporator surface area quickly becomes coated with condensate.

It remains to be seen whether or not the new A/C airflow filters recently added to new designs will keep enough of the "food" from entering the system and becoming attached to the evaporator surfaces to prevent the substantial level of bacterial growth we are seeing otherwise.

 

Thanks guys u really know what ur talking about, but where is this AC drain u are talking about??!! Or should i just have the dealer check it out in my next service since its new.

 

It's not the AC unit... It's your feet....

 

I hadf this problem may still but for now it is under control while the cause may be the AC condensation.
I found somoe mentioned using leather conditioner by zymol on the seats. this seems to workafter a couple of applications . Also I have used a orange oil spray on the interior which give a nice mild non chemical nor overly perfumey smell.
proir to this I followed other suggestions of blowing out the AC exhaust line. used lysol and other stuff including enzyme in air intake with no success. Now that smell is gone ( i hope for good)I can feel the moisture when starting car after AC on .A good suggestion is to run heater for a minute to evaporate moisture build up after AC use.

If it comes back I will try an ozone machine.

while I was trying to beat the smell I called three dealers in nj and none of their service departments said they ever heard of this problem before( I do not believe this or that this problem is an isolated occurance for lexus owners.
I would like to thank the chap who turned me onto the zymol leather cleaner.

 

I have a '95 sc300. Where can I find the drain tube in question?

 

A good way to prevent the A/C smell is to use outside air as much as possible. (Keep the recirc button off.) I know it's hard to do in smog cities such as LA and NYC.