The AC VINEGAR Journey

[kmc0929]

2020 Expedition Limited MAX

I have reached the end of my wits with the Expedition AC Smell Issue. The AC starts with the most pungent vinegar smell possible and goes away once the AC has become cold, usually about 3-4 minutes.

1) Obviously I have changed the cabin air filter, this isn't the source of the smell
2) The dealership has done the TSB that added the elbow to the AC drain, the AC appears to be draining normally (however dealership did say it was not included in the TSB Date Range)
3) I have used the Lysol technique to blast cleaner through the ductwork via the exterior cowl

4) I have drilled a single hole in the evap box and put a full can of the BG Evap Foaming Cleaner into the evaporator and watched it drain out the bottom (this fixed it for 2-3 days)
5) I have drilled a second hole on the high side of the evap box and sprayed 2 cans of the Klima Cleaner Pro into the high or left side of the evap core and then a 3rd can into the low side
*** In both applications the foaming cleaner drains out into a puddle underneath the vehicle***
6) I have used the B&G Fridgi-Fresh spray by spraying it into the blower motor cavity

7) Both holes drilled were cleanly patched using 1/4 sheet metal rubber plugs
8) I have used an endoscope to look into the evap box, the coils look as clean as I would imagine them to be (see photo)
9) The vehicle has a spotless interior

11) We do shut the compressor off about 2-3 minutes prior to parking the vehicle and let it run air through it. I do notice the smell starts to peak when you do this.

Starting to think it's not the EVAP core rather more the ductwork?

*See attached photo of the insertion points for the Evap Cleaning Foam

*Photos with the endoscope are AFTER the application of the foam so they show moisture

*Disregard date stamps on the endo photos, those are wrong

*The smell seem to be only coming from the front AC, however I have NOT foamed / lysol the rear AC unit yet, not positive where the intake / drain is yet...

 

[techdude99]

Wow, that's some thorough troubleshooting and solid attempts to fix the issue!

I tried about half of the fixes mentioned in your post with no success. Three local Ford stores couldn't figure it out.

Unfortunately, this was one of reasons I ended up selling the truck. I'll be following the thread to see if it's finally resolved.

I honestly hope you fix it. Good luck!

 

[BSarchet]

I had this problem in my Taurus and did all the same things you did. The layout of all the parts were very similar to the Expedition. This is a very Ford problem, have not experienced this in other makes of vehicles I’ve owned.

 

[99WhiteC5Coupe]

For years, GM had a similar situation with the musty A/C smell.

GM and ACDelco developed an after-blow module that was added to the HVAC electrical system, which ran the HVAC blower motor for several minutes to dry-out the evaporator.

Later, GM changed their car’s computer which enable a dealer to “turn on” an after-blow feature using the GM Tech-2 device.

I had the after-blow module added to one of my Impala LTZ models, purchased new, which developed the odor. Later, on another Impala LTZ model, the dealer turned-on the after-blow feature. The feature helped considerably to eliminate the musty smell.

I do not know - but does Ford have this after-blow feature programmed into their vehicle computer which would enable the dealer to turn it on?

 

[Password]

Dealer replaced my evap and the smell came back. Now my dash creaks.

 

[kryichek]

Do you run on recycle air all the time? I quit using recycle air and after about 2 weeks or so the smell was gone and hasnt come back.

 

[ROBERT BONNER]

Wow, you tried everything I could think of. I had a Fusion that was parked outside that had the problem and the foam application did the trick forever after a single application. I did that after trying lysol without lasting satisfaction.

You have probably concluded this; but, there must be somewhere in the system that something is growing that you aren't reaching with the various products. My only suggestion would be to look for remote nooks and crannies inside the air handler with the camera and if you find debris/growth target it with foam. A wild card might be to ask a local commercial HVAC company for advice/products.

 

[rd618]

I agree. Another alternative is to use an ozone machine like they do in hospitals, run it on recirculating on battery power with a trickle charger for a few hours.

 

[Fastcar]

I've had that mold smell issue and found that if I close the car and run the heat on max for 1/2 hour problem solved. Was told ya gotta get it dry.

 

[rgbpixels]

2020 Expedition Limited MAX

I have reached the end of my wits with the Expedition AC Smell Issue. The AC starts with the most pungent vinegar smell possible and goes away once the AC has become cold, usually about 3-4 minutes.

1) Obviously I have changed the cabin air filter, this isn't the source of the smell
2) The dealership has done the TSB that added the elbow to the AC drain, the AC appears to be draining normally (however dealership did say it was not included in the TSB Date Range)
3) I have used the Lysol technique to blast cleaner through the ductwork via the exterior cowl

4) I have drilled a single hole in the evap box and put a full can of the BG Evap Foaming Cleaner into the evaporator and watched it drain out the bottom (this fixed it for 2-3 days)
5) I have drilled a second hole on the high side of the evap box and sprayed 2 cans of the Klima Cleaner Pro into the high or left side of the evap core and then a 3rd can into the low side
*** In both applications the foaming cleaner drains out into a puddle underneath the vehicle***
6) I have used the B&G Fridgi-Fresh spray by spraying it into the blower motor cavity

7) Both holes drilled were cleanly patched using 1/4 sheet metal rubber plugs
8) I have used an endoscope to look into the evap box, the coils look as clean as I would imagine them to be (see photo)
9) The vehicle has a spotless interior

11) We do shut the compressor off about 2-3 minutes prior to parking the vehicle and let it run air through it. I do notice the smell starts to peak when you do this.

Starting to think it's not the EVAP core rather more the ductwork?

*See attached photo of the insertion points for the Evap Cleaning Foam

*Photos with the endoscope are AFTER the application of the foam so they show moisture

*Disregard date stamps on the endo photos, those are wrong

*The smell seem to be only coming from the front AC, however I have NOT foamed / lysol the rear AC unit yet, not positive where the intake / drain is yet...

View attachment 81029

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I have the same issue on my 22 Timberline. What is the TSB you reference? My dealer did not mention this.

 

[Mr Big]

The OP's smell may be coming from wet carpet. My Excursion had the issue and drying out the carpet, fixing the drain plug and an ozone machine fixed it.
Now my Expedition has the musty smell when starting the a/c. The cure for me is when it occasionally comes back, run the heat on high for 20 minutes, then spray Lysol down the intake in the cowl. Don't run air on recirculate as it comes back faster. This fixes it, but it always eventually comes back.

 

[Dahammer]

Many years ago, I had a suburban 2004, and my service advisor at the time said that to keep the smell from coming into the cabin, I should pour a bottle of hydrogen peroxide into the cowl. Did it work? Yeah, it did. Every year, I poured a bottle just before summer started and one in the fall.

 

[Fastcar]

Many years ago, I had a suburban 2004, and my service advisor at the time said that to keep the smell from coming into the cabin, I should pour a bottle of hydrogen peroxide into the cowl. Did it work? Yeah, it did. Every year, I poured a bottle just before summer started and one in the fall.

Yeah, that should do it. I guess anything that will kill mold. A mix of 5 to 1 water/pool chlorine will kill mold but the smell may take a day or two to go away.

 

[Jettix2]

Mine too, 2019 Platinum Max, carpet is dry but the nasty A/C smell when we start the car is gross.

 

[Mr Big]

Mine too, 2019 Platinum Max, carpet is dry but the nasty A/C smell when we start the car is gross.

I just did the hydrogen peroxide trick and dumped a 1/2 bottle into the cowl vent holes on passenger side. It seemed to work. I'm sure any kind of chemical that kills bacteria, mildew and mold will work.

 

[Mr Big]

I just did the hydrogen peroxide trick and dumped a 1/2 bottle into the cowl vent holes on passenger side. It seemed to work. I'm sure any kind of chemical that kills bacteria, mildew and mold will work.

UPDATE: It did NOT work. Musty smell still there. I'm going to try the heater method with Lysol spray

 

[Fastcar]

You might want to hold off on the Lysol and try the heat for 20 minutes by it self. The Lysol won't kill mold and it might coat your ducts and more spores will stick do it and perhaps compound your problem.

 

[Mr Big]

You might want to hold off on the Lysol and try the heat for 20 minutes by it self. The Lysol won't kill mold and it might coat your ducts and more spores will stick do it and perhaps compound your problem.

From Lysol: "Lysol can effectively kill mold"

 

[Fastcar]

From Lysol: "Lysol can effectively kill mold"

Okay. Based on experience a bleach or chlorine solution will kill mold. It kills the worst of molds (black mold). There are other types of mold Lysol may kill. As I said before running the ac with the temp up will kill it as mold needs moisture or dampness to live. ymmv

Having said that seems your gonna get some windy weather, hang on tight.

 

[Mr Big]

I've used the heat method for years. The smell comes right back.
So, I'm trying to find a way to really clean it. I watched a video where you take the cowl cover off and somehow get in there to remove any debris that is collecting moisture.
I know one thing for sure, thousands of expedition owners complain about the same smell.
I don't use bleach because of this:
Since bleach is only able to wipe up surface mold spores, it can't seep into materials and effectively kill mold. This also increases the amount of moisture available, allowing deep-rooted mold to thrive rather than be removed. Always remember, mold needs heat/humidity or a water event to thrive.

We are getting the feeder bands of the storm now. It's going to pass right by us about 50+ miles to the west, unless it decides to turn early. So far, it's staying a tropical storm, but it will increase to a hurricane before landfall.