DWP

My wife, the primary driver of our E500, just complained that the air coming into the passenger compartment had the stale/funky smell of dried leaves.

That was a common problem with our previous BMW 528i, especially in the fall, and I had it down to a routine. I would unsnap the covers on the two cabin air intake plenums (just in front of the firewall) and remove the accumulated leaves - somehow they would get in the plenums. Then I would remove the charcoal filters and tap or vacuum them clean/cleaner, then put the filters back in place and snap the plenum covers back on.

That routine doesn't seem to work on our E500, if only because after looking at the car and in the manual, I have no idea where the cabin air plenums and filters are. Where they were on the 528i, on the passenger side the E500 has a box that says "Air Conditioning" and "R134a", which doesn't encourage me to mess with it even if there was an obvious way to open it, which there isn't. On the driver's side is a smaller box with a latch to partially open it and a bunch of wires inside.

So, does the HVAC system on the W211 tend to collect leaves? If so, is it something that the owner can clean out, and where should I look for them?

konigstiger

TSB: P-B-83.30/74b - JUN05
Air conditioning Musty/Moldy Odor Complaints

(1) Wynn’s AIRCOMATIC Ultrasonic A/C Cleaning System together with Wynn’s AIRCO-CLEAN Ultrasonic A/C Treatment is recommended.

(2) If the air conditioning system emits a musty/moldy odor from the vents within 3 months after using the Wynn’s product, a new slanted heater box bottom (part # A211 830 22 03) which allows condensation to drain better and a PU coated evaporator (part # A211 830 01 58) entered production as of VIN A675828 and X171590.

* To reduce the possibility for this condition to reoccur, operate the blower at a higher speed, especially during humid conditions. For cars with a REST function, it also helps to use this feature during humid conditions when parking the car.

khaug

Go here: https://mbworld.org/forums/mercedes-tech-talk/121085-w211-cabin-air-filter-change.html for info on the location of the cabin air filter.

The single nut referenced in the post holds down a loopy piece of black plastic that's a couple of inches in front of the box the filter lives in. Remove the nut, disengage the loop from the screw thread and pull it up and toward the front of the car. You have to be a little assertive here.

I agree with Konigstiger. If you have a funky smell coming from the HVAC system, the most likely source is a mold infestation in the vicinity of the A/C evaporator. In my experience, it's difficult to permanently cure this, if it's the problem, altho I've never tried the ultrasonic method Konigstiger recommends (Our other car, a Toyota, has a bad case of halitosis, so I'd be interested in trying it if I knew where to find it).

Good luck.

-tokz-

* To reduce the possibility for this condition to reoccur, operate the blower at a higher speed, especially during humid conditions. For cars with a REST function, it also helps to use this feature during humid conditions when parking the car.

what do u mean by this?coz my car has the odor too for the first 2-3 mins when i just start a car.. i was thinking about getting it fixed at my local dealer...

thanx..

konigstiger

Follow this procedure after having #1 performed (Wynn's). If the odor comes back have #2 performed (parts). Continue to use this procedure after #2 is performed to stop the odor from reoccurring thereafter.

DWP

Thanks for the replies, all. I probably shouldn't have used the term "funky" to describe the slight odor of the incoming air. It's not really the locker-room smell associated with mildew; it's more like ... dried leaves. So the filter is under the cover on the passenger side that I was reluctant to open ... I don't mind going where others have boldly gone before.

Sacramento's dry, low-humidity climate isn't usually conducive to growing mold or mildew, but since I see some water on the driveway when I stop it to open the gate, the climate control is extracting water from the air, and where there's water, there can be mold/mildew. If I can't kill the odor by leaf removal, I'll try the mold/mildew approach.

-tokz-

sorry to ask about this. but what is Wynn's ?
and
i also didnt quite get what you're talking in #2

can u re state that in a more simple english?

thanx

sl561

DWP, I recently had this same odor problem....also live in Sacramento....so I will be interested to hear what you find. It's not as bad now as it was during late August when it was really hot in my garage. At the time I also had 3 bags of redwood bark sitting in the garage for a while, and thought that might have been the source of the problem, but I can't say that moving the bark outside seemed to help much. Cooler weather does seemed to have helped.

SL

konigstiger

Simply,

You smell an odor coming from the air conditioning (A/C) vents in your 2003 to present E-class vehicle.

You take your car into the dealer and ask them to perform technical service bulletin (TSB) P-B-83.30/74b that was issued June 2005 specifically for A/C odor complaints.

The dealer will clean your A/C system with Wynn’s treatment part #A211 30208 http://www.wynns.be/ (click on products; professional; A/C; then either image) taking about 1 ½ to 2 hours to complete. This treatment should last for at least one year. One treatment per year is covered under warranty.

To reduce the possibility for this condition to reoccur, you’re asked to operate the blower at a higher speed, especially during humid conditions. For cars with a REST function, it also helps to use this feature during humid conditions when parking the car.

If this doesn’t work and the odor returns within three months (providing your car’s VIN is before A6754828 or X171590) your dealer will replace your original heater box bottom with an improved slanted heater box bottom part #A211 830 22 03 which allows the condensation to drain better and your original evaporator will be replaced with a coated evaporator part #A211 830 01 58.

Once again, you’ll be asked to operate the blower at a higher speed, especially during humid conditions. For cars with a REST function, it also helps to use this feature during humid conditions when parking the car.

csumt76

The new a/c treatment seems to fix 99% of the odor issues. We were using another product before that did not work very well at all. Only in a few cases do we end up installing the updated lower section of the heater case and the evaporator.

-tokz-

The REST button in my car doesnt do anything when i press the button..

I tried pressing even when i had the a/c at full blown and nothing happened.

Is it a faulty?

btw thanx for the detailed explanation..

terrylow

The REST function works only when your engine is switched off.

BTW, my car was with the dealer in July this year and the heater pan was changed and a new evaporator was installed. However, the musty smell returned last week!!

Heard the "improved" parts will only be available sometime in November this year.

-tokz-

improved parts?means they gonna change the parts that they used to replace all the radiator???

What actually does the REST function do?

terrylow

Yes, the engineer actually said improved parts like evaporator and software will be available this November.

The REST function actually maintains the temperature of your cabin using residual heat from the engine (your engine cooling system). The fan will continue blowing for about 30 minutes. It is useful when you just need to get out of your car for a short while to get yourself a pack of cigarettes or some popcorn... Unfortunately, this function is redundant in this hot climate we have here in Singapore.

JimPurdy

Has anyone found where to buy the Wynn's products?