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...

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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.