stealth.pilot

My wife seems to drive the car with the AC off from time to time in her C300.

Recently I have found that when I turn on the AC I get for the first few minutes a strong vinegary odor which is horrible. Then it seems to mostly go away.

Took it to dealer today and they are saying they need to change the air filter which apparently wasn't included in the Service B we did last month. In addition they want to clean the evaporative system.

They are quoting $380 for this. That seems ridiculous given the filter is a $50 part.

Any thoughts on what I should do?

DapperStyle

Try to run the AC on auto for a while (like over an hour on a drive). I could've sworn that cabin air filter was part of service B. Any way, if running it on auto (not max cool or whatever) for a while doesn't work try spraying a glycolized air sanitizer spray like ozium and put the system in recirculate until it automatically turns it off.

icanectc

So this happened to me in an 07 you didnt mention what year it is (I think its the 2015 in your sit - if so it was about a year year and an half when my started to do it) But it was fixed under warranty in my case. Apparently in my situation they said the water would start to pool in the evaporation system causing the odor to occur when first turning on and would go away. The smell does get worse if you have same problem.

I don't know why the warranty wouldn't cover the work unless your out of warrantY. The air filter replacement isn't going to solve this. Its being caused by the water pooling. Only way to solve is to clean evaporative system.

Though if your air filter needs replacing you should replace it as well but for other reasons.

Oh they also perfumed the air cycles a few times as well to get any lingering smells out of the vents just in case

joe354

Had the same issue on our previous 13 C350. Dealer indicated there wasn't anything they could do to fix the issue. Recommended having the AC temp around 68-70 v.s. all the way cold. Also take some lysol and spray into the intake vents outside the car bottom of windshield. It seemed to help but never went away completely. The filter replacement really didn't resolve it either. Haven't had the issue on our new C300....

_kkb_

I know the exact smell you are talking about. The AC in my 2012 C250 Coupe used to smell like that every time I turned on the AC. I would call my service advisor and tell him that my car smelled like feet, haha.

As far as I know, all they had to do to fix it was replace the filter, but even then, the smell would come back. Never knew if it was an actual issue with the car's filtration system or not. Hoping that my new C300 Coupe doesn't have the same problem.

A friend of mine who works for Mercedes Benz says that this smell is sometimes caused by having your windows open while you run the AC. Not sure how those two are related, but nevertheless, I make sure to never open my windows while the AC is running.

stealth.pilot

Yes ours is the 2015. I will forward your post to the Service person and if that doesn't work I will try a different dealership.

flycaster

Can't say for sure that the A/C smell situation is an MB engineering fault or not, many who got ATS's had a similar situation. Car would smell moldy, but would eventually get "aired" out after a few minutes of A/C. In the beginning when first being reported with these new models, Cadillac tried all the things (under warranty I might add) mentioned here (filter, sprays, etc.,) all temporary solutions and to no avail. Problem was finally found to be that the receiving end of the condensate drain tube was above the bottom of the pan catching the condensate, thus always leaving water where it shouldn't be and allowing for mold to build up. Solution (under warranty) was to lower the drain to the bottom of the pan. This was a big job that entailed taking a lot of parts out to get to the drain...but Caddy did it at no extra costs...good for them as I had to have this done on my ATS.

EDIT: Only drove my new coupe a 100 miles so far, but yesterday after detailing it, I started to notice a funky smell. Hope it doesn't last. But if it does, and seeing others having the same situation, it could very well be that MB made an engineering/design mistake with their A/C and either they don't own up to it, or haven't found the real cause???

laredotexas1980

Having the same problem... Was yours fixed?

cleankutazn

In my 20 years of driving and having leased BMW's and Mercedes, They all smelled like mold after continual use of the a\c in the summer.

SoDakBenz

The reason u get this smell is cause u run the AC till your done driving. The condensation turns to mold on your condenser and that is what your smelling. If you take a vinegar and water solution in a spray bottle and apray it on the condenser it will get rid of it. Also there is stuff on the market called moldy cheese spray. No joke it exists. That will fix it up also. To prevent it from happening in the future try turning the AC off 5-10 min b4 your drive is done.

stealth.pilot

I don't think it's normal. I've had 7 BMWs, 2 Lexus, 3 Infinitis, a Jag and a Porsche and none of these cars have had this issue.

laredotexas1980

Was yours fix by th dealer??

I was told to turn on the heater for 10 minute full blast and it would get ride of the smell by the local mercedes tech...

SoDakBenz

They did not fix it. They wanted to charge me for it. I just dealt with it for a few months til my lease was up

laredotexas1980

Ok... i setup at appt for next week for service b ... I also told them
About the smell ... If they do anything to it under warranty i will keep u posted.

ibulp91

I have the same problem in my 08 C300! I think it's a very common issue in w204s. Cleaning the evaporation system might solve it! I haven't done it yet, but planning to do

teksurv

I had this issue on my Audi. For MB, wise advice given was to leave the AC system on AUTO, and adjust the temp up or down for comfort. The system will turn on a fan after vehicle shutoff for a while to dry it out. Only if left in AUTO. By leaving my C class and E class in AUTO mode, I've never had this smell. If you prefer to not use AUTO, turn off the AC about 5 minutes before vehicle shutoff.

stealth.pilot

Mine was fixed by the dealer. Required paying for a new filter, and they also cleaned out the parts of the system they could reach. I'm addition sprayed some cleaning sprays into the intake vents to kills of any algae. No smell since.

flycaster

I now believe that my new 2017 coupe does have the "smell." I will try putting on the heat (Yikes! It's only been 90 degree here in FL for much of the year) and then keep the A/C on auto. How does one reach the condenser? The dealer will be next.

carmess

I own a 2016 GLC 300 and complained to dealer when it was new and told they couldn't replicate it but it still occurs and is so bad I have to turn off AC and air out the car. Ridiculous to pay so much for so many problems. Also have squeaky brakes 'they couldn't replicate', media screen stopped working today, and at times it brakes for no reason, but of course they can't replicate that, either!

Cosworth2000

To prevent this you need to run your A/C from time to time even in the winter months. This will prevent mold from gathering in the system plus also help to lube the bearings in your A/C to maintain it's like. I know many do not run their A/C unless it's hot but it's also part of the MB system for clean air so allow it to run. If you have mold or the smell already, you need to clean the system and prevent it. This is a car hack which MB is aware off and if you have a newer model you will see that the A/C always turns on when you push auto.

Terminator1

Rogue-CLK

Penti

Rogue-CLK

Penti