Hello all,

I have a 2009 E550 with about 98000 miles, have owned it about a year.

There is an odor that comes from the cabin heating/ventilation system that I first noticed several months ago. I took it to MB Service at the dealership where I bought the car a few times but I finally gave up on them as they seemed to be just guessing at the issue and generally giving me the run-around.

The odor comes from the heater vents, and smells like plastic that is hot but not burning; there is no smoke. If I put the blower to full speed the odor will soon dissipate, or become diluted sufficiently. If I set the fan speed back to a lower setting the odor will come back.

There are no oil leaks from the engine and I see no obvious sources of the smell in the engine compartment. At first I thought the smell was like hot oil, but it is actually more like hot melted paraffin wax, or melted plastic.

Has anyone got any ideas?

Thanks,

Steve

moved to W211 forum...

Did you look at this post from one week ago?
https://mbworld.org/forums/e-class-w...tic-smell.html
Mike T.

Thank you, I did look at it. I guess I find it hard to believe that a vent flapper could be the cause. This has been going on for months now and the smell is very subtle; there is no smoke. Also, the work to get at the internals of the ventilation system looks to be very involved and extensive and so costly. I do not feel it is a job I could take on myself. I am sure it would be very costly to have the work done at MB Service.

There are other options. There is a foam you can insert in your blower motor area if I am not mistaken, haven't ever done it personally but heard people do it and it works. So I have been told. Talk is cheap, so I'm not 1000% sure.

Inserting foam in my blower motor area sounds exciting

Seriously though... I have the same subtle odor issue... it's not bad enough to consider tearing my dash apart, but your information is intriguing.... does this foam coat the entire ducting or something like that... or does it just mask the smell? Where can I learn more about this option?

This was mine, you are right, not a easy job, when i first notice the smell i said i would not do it, but now that its done, i am so glad i did it

So, how long did it take to do the whole job?
- Steve

cmriv,
What is this foam you speak of, do you have specifics? Or do I just take a can of shaving foam, squirt it in there and hope for the best? ;-)
~ Steve

took me about 6 hours, but i have lots of experience working with this cars, any place you take it to they might not even do just the section i did, they will replace the entire heater box

Remedy a): Model series 169, 245, 203, 209, 211, 219, 215, 220, 230, 171, 164 up to A407859, 251 up to A083326, 216 up to A012332, 221 up to A174161

The above vehicle models are not equipped with recirculated air filtering and biocide-coated evaporator. The following sequence of steps for eliminating odors in vehicles must be strictly adhered to:
- Identification of the cause of the odor with the aid of the diagnosis tree "Odor" from the Technology Guide "Vehicle Climate Control - Troubleshooting - Function - Design - Operation".
(The "Technology Guide - Vehicle Climate Control - Troubleshooting - Function - Design - Operation" is available in pdf format in SDmedia SDS).
If an odor problem still persists after all the possible causes of odor listed in the fault tree have been ruled out:
- Remove filter inspect it and replace it if it is saturated or clogged.

Note: The filter is a maintenance item and is not covered by warranty!
- Cleaning of the evaporator of the air conditioning system in the installed state using "Mercedes-Benz Contra Sept disinfectant cleaner". Further information on the cleaning procedure can be found in S-B-83.30/134.
- Cleaning of the interior using the "ultrasonic atomizer".
Remedy b): Model series 204, 172, 166, 212, 207, 218, 164 as of A407859, 251 as of A083326, 216 as of A012332, 221 as of A174161,

The above vehicle models are equipped with recirculated air filtering and biocide-coated evaporator. In these vehicle models the evaporator can be ruled out as the cause of the odor and cleaning the evaporator is not an appropriate remedial measure. As a result evaporator cleaning is not covered under warranty.

Complaints of odor can only be remedied by replacing the combination filter. The combination filter is a maintenance item and is not covered under warranty.
- It is recommended to replace the combination filter at every scheduled maintenance service at 10,000 miles or every 12 months, whichever occurs first.

- It is required to replace the combination filter at every scheduled maintenance service at 20,000 miles or 24 months, whichever occurs first.






you have a plastic burning smell, however I've heard and been told this dissipates majority of interior cabin smells.

Have you tried getting a car air purifier.... Heard those work in some occassions too.