A/C Smells Like Vinegar (Not Teen Spirit)

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GCATX

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Sitting here, reading this thread, I realize I've had some weird sinus crap going on since about the time I got the truck, almost 2 years ago. Truck also smells when the AC is first turned on. May not be related to sinus issues, who knows.

Quick google search says most mold can be killed at 140-160 degrees. I wonder if doing some full throttle runs on a day when it hits 100 or so, then cranking the heat full blast and letting it sit for a few minutes might have results. I would assume the heater would put out close to what temp the coolant is running? I also have a plug in ozone machine I may run for a few minutes on recirc, I do worry a little about it damaging the plastics though.

I tried the lysol spray into the outside vent a few weeks ago, helped very little.
 

MDJAK

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It's not a "Ford thing"; it's an A/C thing and it can happen with any vehicle that has air conditioning. Certain climates/conditions will exacerbate the common issue in which bacteria, mold, and mildew to accumulate on the evaporator core and create an unpleasent odor, especially when first turning on the A/C on a hot/humid day.

There are plenty of aftermarket chemicals available that will clean the A/C evaporator of contaminates and eliminate any odor, at least for the season.
May not be a ford thing but in the more than 50 vehicles I’ve owned in hot humid NYC, none have ever smelled like a ***** fresh from douching. Not that I’d know what that smells like.
 

lawdog

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It's not a "Ford thing"; it's an A/C thing and it can happen with any vehicle that has air conditioning. Certain climates/conditions will exacerbate the common issue in which bacteria, mold, and mildew to accumulate on the evaporator core and create an unpleasent odor, especially when first turning on the A/C on a hot/humid day.

There are plenty of aftermarket chemicals available that will clean the A/C evaporator of contaminates and eliminate any odor, at least for the season.


I really appreciate what you contribute here, but this is a Ford issue more than any other brand I am aware of. My Raptor does it. My wife's '19 Expedition is starting to do it. My friend's Expedition does it. This forum/the internet is full of Ford cars that do it/complaints about it. I/my wife have owned in my adult life in South Carolina Hondas, Toyotas, Audis, Mercedes, GMCs, BMWs, Lexuses, Saabs, Volvos, VWs, both new and used, and not ONE had the same magnitude/frequency of AC smell/issues as these Fords do. I guess I'm just unlucky that the two brand new Fords I own both do it.

Please give me the name of such chemicals, and please advise your service brethren of them, as well. I have had two dealerships/multiple service advisors here deny the issue/say there's nothing they can do. Thanks in advance.
 

FordTechOne

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May not be a ford thing but in the more than 50 vehicles I’ve owned in hot humid NYC, none have ever smelled like a ***** fresh from douching. Not that I’d know what that smells like.

Check your passenger side carpet for dampness after running the A/C for an extended period. In very humid areas (like NYC as you mention), condensation from the A/C drain tube can seep past the evaporator drain tube seal and cause saturate the carpet/floor mat on the passenger side on 2018-2020 models.

If you find that to be the case, TSB 20-2170 was released to correct the issue. It's less than an hour to repair and requires no interior component removal.
 

FordTechOne

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I really appreciate what you contribute here, but this is a Ford issue more than any other brand I am aware of. My Raptor does it. My wife's '19 Expedition is starting to do it. My friend's Expedition does it. This forum/the internet is full of Ford cars that do it/complaints about it. I/my wife have owned in my adult life in South Carolina Hondas, Toyotas, Audis, Mercedes, GMCs, BMWs, Lexuses, Saabs, Volvos, VWs, both new and used, and not ONE had the same magnitude/frequency of AC smell/issues as these Fords do. I guess I'm just unlucky that the two brand new Fords I own both do it.

Please give me the name of such chemicals, and please advise your service brethren of them, as well. I have had two dealerships/multiple service advisors here deny the issue/say there's nothing they can do. Thanks in advance.

Please see my previous response to MDJAK to inspect for moisture in the passenger side footwell. Are you in a high humidity area? The TSB I mentioned applies to 2018-2020 Expedition as well.

As far as deodorizing, there is a published procedure in the Workshop Manual using Motorcraft A/C Cooling Coil Coating, part number YN-29. Regardless of whether the TSB applies, the odor treatment procedure can still be performed.
 

GCATX

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Please see my previous response to MDJAK to inspect for moisture in the passenger side footwell. Are you in a high humidity area? The TSB I mentioned applies to 2018-2020 Expedition as well.

As far as deodorizing, there is a published procedure in the Workshop Manual using Motorcraft A/C Cooling Coil Coating, part number YN-29. Regardless of whether the TSB applies, the odor treatment procedure can still be performed.
Coil coating? Is this like HVAC coil cleaner spray, or something different? I have a few cans laying around the house. Curious, is there an "easy" way to access the coils?
 

FordTechOne

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Coil coating? Is this like HVAC coil cleaner spray, or something different? I have a few cans laying around the house. Curious, is there an "easy" way to access the coils?

Yes, it's a cleaner, but it also applies a coating to the evaporator to eliminate the re-occurance of buildup. Here are the instructions per the Workshop Manual:

Repair
  1. NOTE: Identify the source of the odor.
    • Check the evaporator core drain tube for restriction.
    • Check the passenger and driver side carpet for moisture. If moisture is found, A/C odor treatment is not necessary. Diagnose for a water leak as needed.
    • Check the cabin air filter and cabin air filter cover for moisture resulting from water bypassing the cowl baffling system. If moisture is found, A/C odor treatment is not necessary. Diagnose for a water leak as needed.
    • Check the cowl top panel and air inlet screen for standing water or foreign material. If necessary, remove the wiper cowl panel to remove any standing water and clean the air inlet screen using a wet/dry vacuum. Refer to appropiate section in Group 501 for the procedure.
  1. Open all vehicle windows and doors.
  1. Make sure the A/C is off.
  1. Select REGISTER mode (A/C off).
  1. Adjust the temperature setting to full warm.
  1. Adjust the blower motor speed to HI.
  1. Run the engine for 25 minutes to dry out the A/C system.
  1. Turn the ignition OFF.
  1. Remove the cabin air filter. Refer to the appropriate section in Group 412 for the procedure.
  1. NOTICE: To avoid damage, do not spill or spray this product on the blower motor speed control.

    Remove the blower motor speed control. Refer to the appropriate section in Group 412 for the procedure.
  1. NOTICE: To avoid damage to the vehicle interior, do not spill or spray this product on any interior surface.

    NOTE: Only Motorcraft® A/C Cooling Coil Coating (YN-29) is approved for use on Ford vehicles. No other coating is approved. Use of other coatings may cause damage to the factory coating and more odor issues.

    Add one full bottle of Motorcraft® A/C Cooling Coil Coating (YN-29) to the A/C Odor Remover Flexible Applicator tool.
    • 258‐62644 A/C Odor Remover Flexible Applicator
      Use the General Equipment: A/C Odor Remover Flexible Applicator
      Material: Motorcraft® A/C Cooling Coil Coating / YN-29
  1. Insert the nozzle into the evaporator housing and direct the spray toward the evaporator core face. Spray the entire evaporator core face until empty.
  1. Install the blower motor speed control. Refer to the appropriate section in Group 412 for the procedure.
  1. Repeat Steps 4 through 8 to cure the cooling coil coating.
  1. Install the cabin air filter. Refer to the appropriate section in Group 412 for the procedure.
 

lawdog

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Please see my previous response to MDJAK to inspect for moisture in the passenger side footwell. Are you in a high humidity area? The TSB I mentioned applies to 2018-2020 Expedition as well.

As far as deodorizing, there is a published procedure in the Workshop Manual using Motorcraft A/C Cooling Coil Coating, part number YN-29. Regardless of whether the TSB applies, the odor treatment procedure can still be performed.

Thanks for this, and, yes, South Carolina is most certainly a high humidity area. NY is a desert compared to here.

Again, I appreciate what you do/offer here, and I wish there were more like you in the dealerships I have dealt with.
 

GCATX

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Sitting here, reading this thread, I realize I've had some weird sinus crap going on since about the time I got the truck, almost 2 years ago. Truck also smells when the AC is first turned on. May not be related to sinus issues, who knows.

Quick google search says most mold can be killed at 140-160 degrees. I wonder if doing some full throttle runs on a day when it hits 100 or so, then cranking the heat full blast and letting it sit for a few minutes might have results. I would assume the heater would put out close to what temp the coolant is running? I also have a plug in ozone machine I may run for a few minutes on recirc, I do worry a little about it damaging the plastics though.

I tried the lysol spray into the outside vent a few weeks ago, helped very little.

So, yesterday when I got home, I turned the heater on full bore and let it idle in the driveway for about 15 minutes. Went back out to the truck and checked the temp at the vents, it was 167F, I switched it over to AC so maybe the hot air would circulate in places it doesn't otherwise, not sure on that. So far today, I haven't noticed any strange smells.

Maybe someone else can try and see if it works. I will report back if anything changes. Or maybe I have the china virus and my sense of smell has been killed.
 

kpecks

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Well, I administered some Ozium into the AC system today. I sprayed it directly into the AC return behind the glove box and let it run for 10 minutes all closed up then opened all the windows for a good while today. Hoping to see what the results will be in the few days.
 
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