2013 ML350 AC Odor Smell Solved, DIY, Pictures - Mercedes-Benz Forum
 
LinkBack Thread Tools Display Modes
post #1 of 7 (permalink) Old 05-11-2017, 04:03 PM Thread Starter
BenzWorld Newbie
 
Date registered: Mar 2017
Vehicle: 2013 ML350
Posts: 2
Mentioned: 0 Post(s)
Quoted: 1 Post(s)
(Thread Starter)
2013 ML350 AC Odor Smell Solved, DIY, Pictures

My AC had a bad odor at start-up, especially when it was hot outside. I read about various ways to eliminate the smell, so I proceeded to do them all plus a couple not mentioned. I removed the intake cover for the system from under the hood area, replaced the one dust filter and two carbon infused air filters with aftermarket filters, and nothing changed. All work was completed before driving the car for the day.

Then I completed these four steps:

1. Sprayed the evaporator (air blows over to change the temperature of the air in the car) with a foaming cleaner. I did it with two different cleaners.

2. Changed all three filters with new Mercedes filters.

3 Used Mr Clean, hand towels, and elbow grease to thoroughly clean all surfaces air passes over from the vent in the hood all the way to the fan.

4. Used an Ozone generator to kill any type of growth in the system.

The entire process took several hours and I am pretty handy when it comes to repairing things.

Details for each step:

Step 1
Cleaning the evaporator probably had the greatest affect on the smell and I also did it twice. The first time I only cleaned the evaporator, which eliminated about half the smell. The second time I complete all four steps and the smell is completely gone.

Step 1A - Remove the access panel under the glove box. There are four torx screws you remove, think it's a size 25 torx screwdriver. Four yellow arrows point to the screws.

Step 1B - Lower the front of the panel down, like opening a door. Yellow letter A, lift up the top lip of this joint to unclip the two panels. Blue Arrow - I slid a thin towel between the plastic parts to protect against scratching the plastic.
Red Arrow - this edge is like a hook to keep the back of the panel above the carpet. Note how it is installed so you can put it back the same way.
Three yellow arrows - metal clips required to hold screws in, make sure they are in the same place when you try to close up the area.
You can also remove this panel completely by removing two electrical connections at the end of the red and yellow wires to the right.

Step 1C - look up behind the AC controls, above the carpet, and you should see a black tube next to the electrical wire grouping. Gently disconnect the tube highlighted by the green arrows by pulling it about an inch toward the door. Do not pull this down toward the floor.

Step 1D - Two pictures. This is what you should see. The green arrow points to the orifice you use to inject the cleaner.

Step 1E - I've done this step twice. I used Kool-It (from Amazon) the first time. It's only 6 ounces, and drained out of the drain tube as expected. It's the only time I've seen any A/C related drainage under the car. The second time I used FJC Foaming A/C Evaporator Cleaner with Odor Control (Amazon). It has 16 ounces of cleaner and much more product - and dirt - drained from the system. Use the plastic tube that came with each product and squirt it up into evaporator box to get as much product to cover as much of the evap as possible. I was able to move the application tube around more with the FJC cleaner as there is much more cleaner in the can. I placed a towel on the floorboard before squirting any product into the system just in case. I also did not squirt any of the product through the fan blades, as illustrated on the Kool-it box. I did not use a cleaner to get the foam out, just let it do it's work and drain by itself. Instructions say to let it sit for 15 minutes, then turn on AC to generate some moisture accumulate in the evap box, which I did.

Step 1F - put it all back together in reverse order. Make sure the lip on the back of the access panel gets over and behind the top of the carpet all along the top of the foot well as well as the metal clips previously noted are properly position over the holes. I didn't do anything special to the air ducts attached to the access panel, they slipped back into place.

Step 2 - I bought and installed new filters from Mercedes. They were $90 for all three from my dealer, just a little more than the after market filters. I completed Step 3 and part of step four after removing the filters and before installing them. I also installed the filters through opening under the hood (well documented on this forum).

Step 3 - I removed the plastic housing component covering the dust filter and cleaned everything cleaned everything from the hood vent all the way to the fan with Mr Clean. My particular intake parts had some blue stuff on them, probably some sort of residue from engine stuff. You have to raise the hood up a little higher than normal (it can go almost vertical) so you can reach all the way down the fan. Instead of spraying cleaner and letting it - and the blue stuff - drain into the system, I first dry wiped all surfaces with a cloth, then wet a clean cloth and wiped everything down a couple times and let it air dry. I used several wet cloths as they ended up with the blue stuff on them and I did not want to smear the stuff all over the place. There are a couple of foam pieces sealing plastic parts. Mine parts had the blue stuff on the foam. I sprayed enough cleaner to soaked the foam parts, compressed the foam to get the cleaner deep into the foam, and carefully compressed and wipe the foam as to not damage the foam pieces while getting the blue stuff off, then let the foam dry out without rinsing out the cleaner. I believe the blue stuff had something to do with the odor problem and thoroughly cleaned all I could see. There is also metal (the firewall) in the duct, which I thoroughly cleaned all the parts and joints as well. I cleaned everything between the fan and the hood.

Step 4 - This took a few hours. I ran an Ozone generator in the duct work from outside the car (see the one I bought). First I put it as close to the fan as possible and covered the opening into the engine compartment with a towel, to force the ozone over the evap and into the car. Two cycles took about an hour. I then installed the plastic piece inside the engine (did not install the filters yet) and ran the Ozone generator for another couple of 30 minute cycles, covering the hole inside the engine compartment to force the ozone into the car. Then I turned to car's fan on low, attaching a battery charger while running the fan, and ran two more 30 minute cycles. After a couple of 30 minute cycles, I reinstalled the filters and all the housing parts, then drove the car, cycling between the lowest temperature AC/high temp heat/low temp AC, to clean out the evap box. Be careful and avoid inhaling the Ozone as it may hurt you.

Probably overkill, but there is no longer any bad odor or smell in my car.
Attached Thumbnails
Click image for larger version

Name:	2017-05-06 0.jpg
Views:	626
Size:	119.9 KB
ID:	2162274   Click image for larger version

Name:	2017-05-06 01.jpg
Views:	464
Size:	41.5 KB
ID:	2162290   Click image for larger version

Name:	2017-05-06 02.jpg
Views:	708
Size:	39.5 KB
ID:	2162298   Click image for larger version

Name:	2017-05-06 03.jpg
Views:	616
Size:	48.2 KB
ID:	2162306   Click image for larger version

Name:	2017-05-06 05.jpg
Views:	561
Size:	40.7 KB
ID:	2162314  

Click image for larger version

Name:	2017-05-06 06.jpg
Views:	760
Size:	66.3 KB
ID:	2162322   Click image for larger version

Name:	2017-05-06-07.jpg
Views:	687
Size:	73.7 KB
ID:	2162330   Click image for larger version

Name:	2017-05-06 09.jpg
Views:	645
Size:	37.1 KB
ID:	2162338   Click image for larger version

Name:	2017-05-06 10.jpg
Views:	740
Size:	40.9 KB
ID:	2162346   Click image for larger version

Name:	Ozone.jpg
Views:	504
Size:	44.7 KB
ID:	2162354  

ArcticDweller and Joey M like this.
hsreed4 is offline  
Sponsored Links
Advertisement
 
post #2 of 7 (permalink) Old 06-21-2017, 08:57 AM
BenzWorld Newbie
 
Date registered: Aug 2016
Posts: 2
Mentioned: 0 Post(s)
Quoted: 0 Post(s)
Great write up! Thanks for posting!
NickW is offline  
post #3 of 7 (permalink) Old 09-18-2017, 09:53 PM
BenzWorld Member
 
Date registered: Dec 2004
Vehicle: '16 GLE350, '14 E350 Sports, '14 GLK350, '02 ML500, '01 ML320 & '96 C280
Location: San Jose, CA
Posts: 123
Mentioned: 0 Post(s)
Quoted: 2 Post(s)
Quote:
Originally Posted by hsreed4 View Post
My AC had a bad odor at start-up, especially when it was hot outside. I read about various ways to eliminate the smell, so I proceeded to do them all plus a couple not mentioned. I removed the intake cover for the system from under the hood area, replaced the one dust filter and two carbon infused air filters with aftermarket filters, and nothing changed. All work was completed before driving the car for the day.

Then I completed these four steps:

1. Sprayed the evaporator (air blows over to change the temperature of the air in the car) with a foaming cleaner. I did it with two different cleaners.

2. Changed all three filters with new Mercedes filters.

3 Used Mr Clean, hand towels, and elbow grease to thoroughly clean all surfaces air passes over from the vent in the hood all the way to the fan.

4. Used an Ozone generator to kill any type of growth in the system.

The entire process took several hours and I am pretty handy when it comes to repairing things.

Details for each step:

Step 1
Cleaning the evaporator probably had the greatest affect on the smell and I also did it twice. The first time I only cleaned the evaporator, which eliminated about half the smell. The second time I complete all four steps and the smell is completely gone.

Step 1A - Remove the access panel under the glove box. There are four torx screws you remove, think it's a size 25 torx screwdriver. Four yellow arrows point to the screws.

Step 1B - Lower the front of the panel down, like opening a door. Yellow letter A, lift up the top lip of this joint to unclip the two panels. Blue Arrow - I slid a thin towel between the plastic parts to protect against scratching the plastic.
Red Arrow - this edge is like a hook to keep the back of the panel above the carpet. Note how it is installed so you can put it back the same way.
Three yellow arrows - metal clips required to hold screws in, make sure they are in the same place when you try to close up the area.
You can also remove this panel completely by removing two electrical connections at the end of the red and yellow wires to the right.

Step 1C - look up behind the AC controls, above the carpet, and you should see a black tube next to the electrical wire grouping. Gently disconnect the tube highlighted by the green arrows by pulling it about an inch toward the door. Do not pull this down toward the floor.

Step 1D - Two pictures. This is what you should see. The green arrow points to the orifice you use to inject the cleaner.

Step 1E - I've done this step twice. I used Kool-It (from Amazon) the first time. It's only 6 ounces, and drained out of the drain tube as expected. It's the only time I've seen any A/C related drainage under the car. The second time I used FJC Foaming A/C Evaporator Cleaner with Odor Control (Amazon). It has 16 ounces of cleaner and much more product - and dirt - drained from the system. Use the plastic tube that came with each product and squirt it up into evaporator box to get as much product to cover as much of the evap as possible. I was able to move the application tube around more with the FJC cleaner as there is much more cleaner in the can. I placed a towel on the floorboard before squirting any product into the system just in case. I also did not squirt any of the product through the fan blades, as illustrated on the Kool-it box. I did not use a cleaner to get the foam out, just let it do it's work and drain by itself. Instructions say to let it sit for 15 minutes, then turn on AC to generate some moisture accumulate in the evap box, which I did.

Step 1F - put it all back together in reverse order. Make sure the lip on the back of the access panel gets over and behind the top of the carpet all along the top of the foot well as well as the metal clips previously noted are properly position over the holes. I didn't do anything special to the air ducts attached to the access panel, they slipped back into place.

Step 2 - I bought and installed new filters from Mercedes. They were $90 for all three from my dealer, just a little more than the after market filters. I completed Step 3 and part of step four after removing the filters and before installing them. I also installed the filters through opening under the hood (well documented on this forum).

Step 3 - I removed the plastic housing component covering the dust filter and cleaned everything cleaned everything from the hood vent all the way to the fan with Mr Clean. My particular intake parts had some blue stuff on them, probably some sort of residue from engine stuff. You have to raise the hood up a little higher than normal (it can go almost vertical) so you can reach all the way down the fan. Instead of spraying cleaner and letting it - and the blue stuff - drain into the system, I first dry wiped all surfaces with a cloth, then wet a clean cloth and wiped everything down a couple times and let it air dry. I used several wet cloths as they ended up with the blue stuff on them and I did not want to smear the stuff all over the place. There are a couple of foam pieces sealing plastic parts. Mine parts had the blue stuff on the foam. I sprayed enough cleaner to soaked the foam parts, compressed the foam to get the cleaner deep into the foam, and carefully compressed and wipe the foam as to not damage the foam pieces while getting the blue stuff off, then let the foam dry out without rinsing out the cleaner. I believe the blue stuff had something to do with the odor problem and thoroughly cleaned all I could see. There is also metal (the firewall) in the duct, which I thoroughly cleaned all the parts and joints as well. I cleaned everything between the fan and the hood.

Step 4 - This took a few hours. I ran an Ozone generator in the duct work from outside the car (see the one I bought). First I put it as close to the fan as possible and covered the opening into the engine compartment with a towel, to force the ozone over the evap and into the car. Two cycles took about an hour. I then installed the plastic piece inside the engine (did not install the filters yet) and ran the Ozone generator for another couple of 30 minute cycles, covering the hole inside the engine compartment to force the ozone into the car. Then I turned to car's fan on low, attaching a battery charger while running the fan, and ran two more 30 minute cycles. After a couple of 30 minute cycles, I reinstalled the filters and all the housing parts, then drove the car, cycling between the lowest temperature AC/high temp heat/low temp AC, to clean out the evap box. Be careful and avoid inhaling the Ozone as it may hurt you.

Probably overkill, but there is no longer any bad odor or smell in my car.

Excellent write up, do you have a youtube channel ?

2014 E350 Sport White
2014 GLK350 White
2008 E350 PANORAMIC ROOF, THE PREMIUM II PKG, PARKTRONIC
2001 ML320 White / 19" GL wheels
1996 C280 White Sport / 18" AMG
H&R sport springs
Koni Adjustable Shock
cupertino is offline  
Sponsored Links
Advertisement
 
post #4 of 7 (permalink) Old 09-25-2017, 09:56 AM Thread Starter
BenzWorld Newbie
 
Date registered: Mar 2017
Vehicle: 2013 ML350
Posts: 2
Mentioned: 0 Post(s)
Quoted: 1 Post(s)
(Thread Starter)
No. I don't have the time nor do I do very much of this. Just thought I would share this particular item here as the dealer wanted $300 for a treatment and said it would probably come back in 3 months. It was also hard to research the fix on the internet.

I also haven't had a whiff of the odor this entire summer. Summer was always the worst. I think the blue stuff in the intake just before the fan, where the two filters are located, was the source of the odor and it gets drawn into and stuck to the heat exchange, the thing you squirt the foaming cleaner on through the tube under the dash.

I keep a small carbon filter - natural deodorizer - in the bottom of the air intake now (picture 8).
hsreed4 is offline  
post #5 of 7 (permalink) Old 06-05-2019, 09:21 AM
BenzWorld Junior Member
 
Date registered: Apr 2013
Vehicle: 2013 GL 450
Location: Boston, MA
Posts: 30
Mentioned: 0 Post(s)
Quoted: 2 Post(s)
Hi hsreed,

I was wondering if your solution was permanent to remove the smell from your ML350 or, did the smell return?

Last fall 2018 I tried your method (thank you) and sprayed both spray can products you mentioned in your write up into the evaporator. I saw all kinds of fluid eventually come out the evaporator drain under the car so I assume it was going to the right place.

The car seemed to smell a little better afterward but it did still smell on warmer winter days and now, in the late spring, it's really bad again.

I also replaced the 3 cabin filters which did not seem to smell themselves.
I dont think this is an animal issue as it's been going on in warmer weather for a few years.

Does anyone know how to get AC vent smells out of these vehicles?
ihart is offline  
post #6 of 7 (permalink) Old 06-09-2019, 02:25 PM
BenzWorld Member
 
peter2772000's Avatar
 
Date registered: Nov 2017
Vehicle: 2007 FJ, 2012 BMW X6, 2013 ML350 BT
Location: Montreal Qc/Cape Coral FL
Posts: 86
Mentioned: 0 Post(s)
Quoted: 17 Post(s)
The trick is to shut off the a/c minutes before you reach your destination, all the while running your fan at high speed in order to dry the evaporator
peter2772000 is offline  
post #7 of 7 (permalink) Old Today, 07:53 PM
BenzWorld Junior Member
 
Date registered: Feb 2019
Posts: 11
Mentioned: 0 Post(s)
Quoted: 6 Post(s)
If you still have the smell let me know, I can help you get rid of that
gramen is offline  
Sponsored Links
Advertisement
 
Reply

  Mercedes-Benz Forum > Mercedes-Benz Vans/Trucks/SUV/Others > W166 M-Class / GLE-Class

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Mercedes-Benz Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 3 (0 members and 3 guests)
 



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 

Title goes here

close
video goes here
description goes here. Read Full Story
For the best viewing experience please update your browser to Google Chrome