I have a 2006 E350 that has developed a noticeable musty/mold smell emitting from the a/c system. Car is under warranty, dealership is just changing parts in hopes of stumbling across the problem. To date they have changed the cabin air filter and done the service bulletin on system clean-out, replaced the condenser (left out some MAJOR, blue, 12 point bolts found under the mat). All seat bolts are installed and are black in color.

Anyway, now I notice a distinct mold smell coming from the front, outside area of the car when it's parked in the garage. I have been on my knees crawling all around the car and cannot nail the source. The dealership service writer is useless as I probably could leave a voicemail for the mechanic and probably do better.

Car always garaged in Palm Beach area.

Any clues?

Thanks.

Is the A/C running non-stop or do you turn it off every now and then?

Driven daily, 2006 with 38,454 miles. My wife sometimes has the windows down on the nice days..............like the last two weeks.

My 560 has 218,000 on it with the a/c on 24/7. No problems.

This is a clip from a google search on Mold Airconditioning Car

Signs of Air Conditioning Problems


Wet carpeting on hot, humid days can indicate a clogged air conditioner drain. When the drain is working correctly you'll see a good amount of water dripping to the pavement under the vehicle after you park.

A vibration or abnormal noise when the fan is on could indicate debris in the blower fan (mice like to make nests in fans).

A reduced amount of air coming out the vents, especially if it happens after driving for awhile, might mean the air conditioner's evaporator is freezing up.

A musty or mildewy odor when the fan is first turned on, or all the time when the system is running, can indicate that mold or mildew is growing in the evaporator box.
You can reduce the buildup of mold and mildew by turning the A/C recirculation switch off when you park the vehicle. If your vehicle doesn't have a recirculation switch, turn the A/C switch away from the "Max Air" position when you park.

Some vehicles will still develop a musty odor--even when you take these steps. Many service departments offer a cleaning procedure for the evaporator.


A Few More Auto Air Conditioning Tips
When you get into a hot car, roll your windows down a little for the first few blocks. If you have a recirculation button, make sure it's turned off. After the hot air is gone, turn recirc on to get the most out of your system.

We're all concerned with fuel mileage, but modern auto air conditioning systems are pretty efficient. Turning the A/C off results in minimal gas savings.
If you discover a problem, take the vehicle to a trusted technician.

Steve

Steve,

I see many good tips on how to prevent this from happening again. Also, I see I have been using the wrong terms in describing what has been done by the dealership. It was the evaporator that was changed because they tore apart the entire dash and center console. They also indicate they cleaned the evap pan while in there. I think I said it was the condenser, which is in the engine compartment. My mistake.

My 560 dumps water in the garage after driving but I do not recall that happening with the 350. I thought that was an advantage or feature of this model and that it dumps the water, after a few miles, during the next start-up. I guess it would be described as a holding pan or tank.

from the evaporator case to the outside on the bottom of the car. If the A/C is run for anytime at all in FL, water will come out of those because the evaporator is acting as a de-humidifier.

you can simply turn off the A/C but leave the fan on or at least get out of the recirculate mode) 2-3 minutes before shutting off the car, to get some fresh air and dry things out a bit before shutdown. Pick up a disinfectant that you can spray into the inside air intake in the passenger side footwell with the A/C on in recirculate mode. Spray lysol where the fresh air enters the A/C system.

Another tip:
See to it that all parts inside the car are always dry. That's why I kept all my Mercedes 240D parts such as carpets dry at all times to avoid musty smell inside the car.

If Your Talking About The Musty Odor When Turning On The Ac..its Moisture\mold That Has Form In The Evaporator Housing In The Dashboard....the Previous Campaigns For The Wynns Airco Cleaning System Have Been Discontinued And There Is A New Campaign Available That Should Eliminate This Odor, In Any Case If It Doesnt They Should Replace The Evaporator Housing If The Odor Is Not Diminished.

Is it possible an insulation blanket on the bottom of the car could have absorbed moisture from the plugged drain? The real mold smell, right now, appears to be coming from outside the interior and somewhere from the front half of the car. The car is parked in the garage with the windows up and upon entering the garage after the car has been parked, the smell is there, but not inside the car. To me, the ventilation system is acceptable since they cleaned the drain housing. Earlier, I said they changed the evaporator. They only removed it to clean the housing, then re-installed with new o-rings. They indicate the heater box was inspected for mold and none found.

Wife is out racking up more miles right now. I will tell her to leave the a/c running until shut-down in the garage to see if water drains. Do I understand there is not a holding or delay in the drain process?

Thanks to all.

Would someone really go to all the trouble to remove an evaporator and then just clean the old one and put it back in?

Just curious, what did this cost?

Also, there would be no holding tank...the idea is to get rid of the water - not save it for nasties to grow in.

__________________
2012 E350
2006 Callaway SC560

Brew,

Dumping the water makes the most sense to me, also. It was the dealership that removed the evap so they could remove the heater box to clean it. I have no real knowledge on what must be removed to get at these parts, I'm just reading it off the service invoice. They removed the crash bar, wiper motor, yadda, yadda. I see they also removed the lower engine cover. I'm just trying to get a lead on the source. All still under warranty.



Thanks, again.