Carbon soot under car. Any ideas why?

[gwcorris]

I have a 2020 Aviator reserve. I find drips under the car, near the rear of the engine, which leaves a soot-like residue when dry.
The dealer said it comes from an exhaust drain hole; however, I have never seen anything like this on other cars.
Could it be from the turbos?
Has anyone else seen this?

 

[bbf2530]

I have a 2020 Aviator reserve. I find drips under the car, near the rear of the engine, which leaves a soot-like residue when dry.
The dealer said it comes from an exhaust drain hole; however, I have never seen anything like this on other cars.
Could it be from the turbos?
Has anyone else seen this?

Hi gwcorris. While I can not determine what is causing the spots you are referring to, auto exhausts do have drain holes to allow drainage of exhaust condensation.

Generally speaking, if you were leaking something from "the turbos", you would have driveability and other issues.

If it is water (no oily residue?), then it is most likely what your Dealer stated, drainage from the exhaust system.

Good luck with your new Aviator.

 

[jkeaton]

What he said.... ^^

 

[eylarson]

Noticed the same on ours. Most likely from the A/C condensation drain. The end of the drain tube picks up road grime the condensate washes it off. With an auto temp HVAC system the A/C compressor runs on demand automatically unless you turn it off with the A/C switch on the climate control panel.

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[gwcorris]

It's just odd that I've never seen anything like this under our other vehicles.
Other than that, we really love the car.

 

[jkeaton]

It's just odd that I've never seen anything like this under our other vehicles.
Other than that, we really love the car.

All cars are not the same.

 

[Farfelue]

Hi gwcorris. While I can not determine what is causing the spots you are referring to, auto exhausts do have drain holes to allow drainage of exhaust condensation.

Generally speaking, if you were leaking something from "the turbos", you would have driveability and other issues.

If it is water (no oily residue?), then it is most likely what your Dealer stated, drainage from the exhaust system.

Good luck with your new Aviator.

 

[Farfelue]

I have the same problem with my 2020 Aviator Reserve -- three carbon spots on garage floor, below joints in the exhaust pipes. These are not weep holes like the mufflers have.
Dealer put the car up on a lift and confirmed the leaks. At first, said this was normal. Not so! Never saw this before on any of the 15 new cars I have owned over 50+ years, including several Lincolns. Now waiting for a fix . . . .

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[jkeaton]

I have the same problem with my 2020 Aviator Reserve -- three carbon spots on garage floor, below joints in the exhaust pipes. These are not weep holes like the mufflers have.
Dealer put the car up on a lift and confirmed the leaks. At first, said this was normal. Not so! Never saw this before on any of the 15 new cars I have owned over 50+ years, including several Lincolns. Now waiting for a fix . . . .

Weld the joints if you don't like it. Then it will just drip out of the tailpipe opening. OR......drive it hard every once and awhile, open it up, blow all the carbon deposits out of the exhaust system. You do realize fuel is carbon based.

 

[Farfelue]

Weld the joints if you don't like it. Then it will just drip out of the tailpipe opening. OR......drive it hard every once and awhile, open it up, blow all the carbon deposits out of the exhaust system. You do realize fuel is carbon based.

Yes, I surely don't like it. It should not be like that. Have been working on cars for over 65 years, now, including all kinds of exhaust system components.
Nothing is supposed to leak from those exhaust pipe section joints, especially in that area! This is not like the weep holes in mufflers, designed to remove accumulated moisture that has not been burned out.
P.S. I do drive the car hard on occasion -- I enjoy punching the 400 hp. to get up to speed when entering an expressway (Reminiscent of earlier days and one of my Corvettes with the racing engine . . . .)
Thanks for your good comments.

 

[RAINEY]

My 2018 F150 had the same thing. Little soot spots on the floor in the garage. Dealer told be is the drains for moisture. I think if that;s coming out so can CO2. I've never had another vehicle do that. So far my 21 Aviator GT is not doing it.

 

[mgd]

I have a 2020 Aviator reserve. I find drips under the car, near the rear of the engine, which leaves a soot-like residue when dry.
The dealer said it comes from an exhaust drain hole; however, I have never seen anything like this on other cars.
Could it be from the turbos?
Has anyone else seen this?

Yes I also had this problem. Exact same location. The dealer said the air filters we extremely dirty. Only have 7,000 miles on car, always garaged and most are freeway miles. So I said change the filters but could not believe this had anything to do with the soot like drips.......However, brought the car home and no more soot-like drips. Don't understand this. Wonder if something happened at the assembly plant which would cause this......the soot - drips started the same week we purchased the aviator. Let me know what you find out re the air filters if by any chance your are dirty. No reason why the air filters should have been dirty from day one......But they said the air filters were really bad when we had them changed at 7k miles

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[Corsart]

Yes I also had this problem. Exact same location. The dealer said the air filters we extremely dirty. Only have 7,000 miles on car, always garaged and most are freeway miles. So I said change the filters but could not believe this had anything to do with the soot like drips.......However, brought the car home and no more soot-like drips. Don't understand this. Wonder if something happened at the assembly plant which would cause this......the soot - drips started the same week we purchased the aviator. Let me know what you find out re the air filters if by any chance your are dirty. No reason why the air filters should have been dirty from day one......But they said the air filters were really bad when we had them changed at 7k miles

Dirty air filters would cause breathing problems for the engine which you might feel as stumbling, but not carbon drips. And especially after 7000 regular use miles, this was a bogus explanation.

Direct injection engines (like yours) typically throw off more carbon. So, to avoid blackening the back of the car, manufacturers place holes in the bottom of the exhaust (anywhere) to allow the carbon deposits to fall before reaching the tail pipe opening.

 

[mgd]

Dirty air filters would cause breathing problems for the engine which you might feel as stumbling, but not carbon drips. And especially after 7000 regular use miles, this was a bogus explanation.

Direct injection engines (like yours) typically throw off more carbon. So, to avoid blackening the back of the car, manufacturers place holes in the bottom of the exhaust (anywhere) to allow the carbon deposits to fall before reaching the tail pipe opening.

THANKS - I think I used the wrong term. The filters which were changed out were the cabin filters for the air circulation inside the car. The air filters for the engine were ok and did not need to be changed. So - not sure why the cabin filters were as dirty as the dealer stated. They may have done something else to fix the soot spots on the garage floor. In any event, got the Aviator back, and no more soot spots on garage floor. There is nothing on the service report regarding anything else they did related to the soot spots.

 

[Corsart]

THANKS - I think I used the wrong term. The filters which were changed out were the cabin filters for the air circulation inside the car. The air filters for the engine were ok and did not need to be changed. So - not sure why the cabin filters were as dirty as the dealer stated. They may have done something else to fix the soot spots on the garage floor. In any event, got the Aviator back, and no more soot spots on garage floor. There is nothing on the service report regarding anything else they did related to the soot spots.

LOL! Dirty cabin filters and soot?! Did you ask how that would work? There's no connection between the cabin air filter (which is in the ductwork for the HVAC) and the underside, nor would it's clogging....after 7000 miles?....result in soot anywhere, unless you were driving thru a coal mine with the windows open! So, you got a new cabin filter (hopefully at no charge) but your original concern went unaddressed.

Here's what I would do: I'd put down white paper under the exhaust, let the car run for a few minutes, shut it off, and when it cools down, get under there with a flashlight and look to see where the leakage is from. If there are easily noticed, machined holes, you're fine. If it's coming from a clamp or joint, make another appt. and show them what you found and where it came from.

"Dirty cabin filters", c'mon.