Stinky Air Conditioning

[82DMC12]

Hi group,

I have a 1994 Lexus ES300. A year ago I replaced the expansion valve on the evaporator core under the dash. Not long after that I began having a foul odor coming from my A/C. I think I must have disturbed some mold or something under there. I know my A/C drain isn't plugged because it always leaves copious amounts of water under the car whenever I am idling with the A/C on.

I have tried using a product called PureAir from Checker Auto, as well as spraying lysol down the air intake duct. It only works for a short time before the odor is back. I have also ran hot water through the vent and out the drain to no effect.

What else should I do? I was thinking mixing up some bleach and hot water and pouring it down there but I am afraid of what it might do to things that aren't mold, as well as leaking onto my carpets.

Andy

 

[johnd]

I live in a damp climate and ac odors are always a problem. I always cut off my ac and open the fresh air vent the last mile or so going home to dry it out. I never have that problem anymore. My wife isn't quite as faithful to this procedure and every now and again I have to squirt Febreeze in the air intake to freshen it up.

 

[punisher]

Just some random stuff:

Turn your AC compressor off (leave blower running)a minute of so before you park the car. This will remove a large portion of the condensation on the evap core and the foam seals around the evap core. Most of the smell comes from mold and mildew growing on the foam seals around the evap and the blend/control doors. At the dealership we removed a few evap cores and soaked them in diluted Clorox, and reinstalled them with all new seals. Changing the seal material fixed the problem for the most part.

FoMoCo made a neat product that killed and encapsulated the mold in evap housings. Cannot remember the specific name for it though, but it came in a pint bottle, expensive. It was sprayed on the evap through the blower motor resistor mount, or we drilled a small hole in the evap housing and sprayed it through that.

Might be a good idea to check to see if there are any TSBs or service bulletins for the problem. You never know, there might be a factory/permanent fix for the problem.

EDIT: Left to get a bite to eat and beaten by johnd.

 

[PandaBear]

Toyota has a TSB that suggest spraying IPA alcohol into the evaporator core, and brush it with dental brush (those stick with nylon spikes all around it).

Clorox makes an antibacterial spray that works pretty well, but stinks for a while.

 

[charlie_bravo]

We had a 98 Camry with the same problem. Adding to the other posts above...
We'd pour a Pinesol mix through the vents/openings just below the windshield wipers. That would help also.

 

[porcupine73]

+5 on the let it run on high for a few minutes before shutting down after running A/C. Usually a couple miles from home I shut off A.C. and let it blow on high til I get home. Otherwise I can start to smell it. No smell at all if it's let run for a few minutes before shutting down.

Keeping you car clean can help. A lot of times it's pet hair, dust bunnies, etc., on the core that collect and then get wet and then mold starts to grow and it just stinks like mad. There's a lot of treatments available; I think consumer reports did a test some time back.

Note too that many vehicles run the A/c when in defrost too so that's something to keep in mind.

 

[mcrn]

Get yourself an ozonator. They are not cheap but they will knock that smell out for sure. It is something like 30 times more effective on mold and mildew than bleach. If it is a organic smell the ozonator will take care of the smell. Just keep yourself or pets or anything out of the car while its running.

 

[82DMC12]

Hey guys thanks for all the help. For the last two days I have driven around town with the fan on but no A/C compressor (luckily it has been cool outside!). The smell has gone down considerably. Tomorrow I will start running the A/C again but running just the fan for the last few blocks. Might try the pine sol thing too.

As for the ozone generator. It just so happens that I have easy access to one (I am the district manager for a dry cleaning company). However I don't see how it will either kill the mold or bacteria or permanantly get rid of the odor. Positively charged Ozone attaches to negatively charged particles in the air (like odor molecules) and the combined weight causes the new molecule to fall to the floor. I don't believe that will fix the root problem. Not only that, but how would I inject ozone into the A/C system? Do you propose aiming the generator into my windshield vent while the fan is running? If you put the generator in the car, surely it will not fix the root problem.

Andy

 

[mcrn]

It will not fix the root problem but it will get rid of any mold or mildew thats in your car. It changes 02 into 03 and then the 3rd oxygen molecule looks to bond to other carbon based molecules and somehow breaks them down, something like that

. However I know for a fact that it works. I had to get rid of a smell in my truck after a container of water spilled and I didn't know it so it started to get that moldy smell the ozonator got rid of the smell. I had to call a few auto detailers to see how they got rid of smells and one place mentioned the ozonator they said they would charge me 30 bucks for them to run it in my car for as long as needed ( up to 3 hours which they said no smell would be around for sure after 3 hours )they said just let it run in the car with the A/C running if the smell was in your A/C. So that would be what I would try. But to fix the root of the problem is something else. Have you felt of your floor to see if the carpet is wet? I had a leak from behind the dash onto my carpet and the A/C pick up was near the front carpet and would pick up the odor. Hope that helps.

 

[1sttruck]

Strong chemical smell, but Lysol works better than a lot of products on 'bugs'. We use to use it and 70% alcohol in a microbiology lab that I worked in for general clean up. Just make sure that whatever you use a disinfectant and not just a deodorant.