Weird smell! A/C works well, maybe standing water?

[CMarron]

2012 SL with 21K miles, bought used just 1 month ago. Everything works great on the vehicle and I really like it. Recently, being that we are getting warm weather in the Bay Area, I've been using the A/C however as of late I've started to smell a funny order that likens to standing water. Anyone have any ideas what this might be? I suppose the A/C condensation line might not be releasing the water completely and some of it is getting pooled somewhere. Any ideas what I can check before I take it to the mechanic?

Thanks folks. I have since replaced the cabin air filter with a FRAM Breeze Baking Soda type and previous filter had some dust however it was not completely black and did not have evidence of mildew.

Next, I am going to check the water discharge tube/valve and make sure that is not blocked and check for standing water on the front floor on driver's side. If not blocked, I am going to clean out the evaporator coils with a product like Frigi-Fresh as recommended in one of the posts on this thread. All this while changing my AC habits and selecting the non-recirculate on turning off AC one mile before my destination. I will do this for about 2 weeks and report results. Standby.

Update:

As per the recommendations from the group I purchased an AC coil cleaner, Lubegard's Kool-It Evaporator and Heater Foam Cleaner (2 bottles), then I located the AC drain hose, which I did not have a jack to prop it up so I found where the hose connected to the evaporator housing. It is located on the driver's side in the center mount by the gas petal. There is a plastic panel that is help by a plastic crew which when turned a quarter turn it will allow you to pop it out with a flat screw driver. You then remove that small panel and you will find 2 hoses, it is the one going down. You can see it connected to the evaporator housing by pressure. I pulled it out with a simply tug and then blew in it to dislodge any debris. The open hole in the housing is where you will put in the hose provided by the Kool-It product, just follow instructions on the canister. I used two cans to make sure that stuff really go in there. When you start pumping that stuff in there make sure the hole in the housing is temporarily plugged with paper towels so that the foam doesn't escape outward. Once you are done with the foam, quickly re-insert the AC drain hose back and continue to follow the instructions to complete the process. Then put everything back together. Don't forget to place some type of recepticle beneath the car to catch the stuff that comes out of the AC drain hose. Oops, almost forgot, I removed my air cabin filter before I pumped it with Kool-It.

The smell is gone! Thanks everyone for providing your help with this. I hope this write up helps someone else too.

 

[LeftieBiker]

Make sure that you don't use Recirculate 100% of the time, and open the fresh air circuit for a minute before you turn the A/C off. This is a common issue with ICE vehicles as well. Mold can build up on the evaporator coils if they don't get fresh water from the air "rinsing" them regularly or if the drain isn't working properly. If the latter is happening, there will be water on the front floor, usually the driver's side, IIRC. If Lysol bothers you, you can also spray a mixture of vodka and apple cider (or white wine, I suppose) vinegar into the air intake, avoiding getting it on the car's surfaces. I used to do that with our cars when the smell started.

 

[Nubo]

The water discharge tube/valve could be blocked. So certainly check that first. Even if not, moisture on the evaporator coils or in the housing can attract dust, and encourage growth of mildew. A best practice is to turn off the AC and let the fan dry things out for a few minutes as you approach your destination.

For AC mildew, there are products such as Frigi-Fresh that will help kill the mildew and clean out the coils. Or a cheaper alternative would be Lysol spray (entire can). I have used the Lysol approach in the past with success.

 

[LeftieBiker]

Or a cheaper alternative would be Lysol spray (entire can).

Maybe for extreme cases, but that stuff is toxic enough in smaller amounts! When I used it I had success with maybe 1/10th a can.

 

[Darryl]

A best practice is to turn off the AC and let the fan dry things out for a few minutes as you approach your destination.

Good advice! This has been my practice to turn off recirculation and the A/C in the last 1/2 mile or so from my destination. Or if I forget, I sit with the car on for a while with these off while I wait for things to get dried out at my destination before getting out.

 

[baustin]

Have you checked the air filter to see if it needs replaced?

 

[oko]

I've had this issue for 3 years (on a 3.5 years old car) in Texas. When I changed the cabin filter, one side of it was completely black, covered with mold (or mildew?). I tried many things, including turning off A/C a few minutes early, spraying hydrogen peroxide, spraying mold-remover (was a very bad idea, caused white spots in all over the place). Nothing helped.

I'll try Lysol next time. There are also some products on Amazon claiming to fix this, but I never tried.

 

[gshepherd]

Wonder if an ozone treatment would help, like what can be done to remove odors from a car interior... maybe find a dealer or detail shop that can ozone treat the interior with the climate control on recirculate during the process.

Another thought is to follow the instructions for gaining access to the blower housing, removing the blower (and air filter) and giving that whole intake area a good cleaning. There might be all sorts of debris in there as it isn't screen out much from the outside air intakes at the base of the windshield. Recently, one of the members here found a dead mouse. It's a squirrel cage blower; the mouse should have known better. Ha. Haha.

This has been such a common problem with vehicles, especially in areas with higher humidity. I too have developed a procedure of turning the A/C off and fan up as I approach my destination. That's been my habit now even before the LEAF. Nobody like stinky A/C, well, except perhaps the companies that sell equally stinky air "fresheners".