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Old Jan 13, 2007 | 02:35 PM
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When I start my 79, a black liquid substance shoots out the tail pipes. If someone could tell me why it is doing that and a way to fix it, I would really appreciate it.
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Old Jan 13, 2007 | 02:40 PM
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Soot and condensation maybe??

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Old Jan 13, 2007 | 02:42 PM
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Why is it doing that? Is the car alright?
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Old Jan 13, 2007 | 05:45 PM
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Originally Posted by Doug Maitlen
When I start my 79, a black liquid substance shoots out the tail pipes. If someone could tell me why it is doing that and a way to fix it, I would really appreciate it.
my tvr griffith used to do that sometimes...i think it's condensation mixed with combustion residues, i'm not sure but i think it happens when the day before you drive into a traffic jams and anyway idle the car in traffic for long without revving it sufficiently for long...i dont think it's a bad sign for the engine anyway
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Old Jan 13, 2007 | 05:57 PM
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Nothing wrong with it. Pretty normal, although excessive soot might indicate a mixture that is too rich...
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Old Jan 13, 2007 | 05:58 PM
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Originally Posted by Doug Maitlen
When I start my 79, a black liquid substance shoots out the tail pipes. If someone could tell me why it is doing that and a way to fix it, I would really appreciate it.
Water vapor is a by-product of combustion. Most noticable in cool air as it condenses. The black is carbon, proably resulting from a rich condition such as the choke is on.
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Old Jan 13, 2007 | 06:31 PM
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Originally Posted by Big2Bird
Water vapor is a by-product of combustion. Most noticable in cool air as it condenses. The black is carbon, proably resulting from a rich condition such as the choke is on.


Condensation is perfectly normal for engines, its a byproduct of combustion. Once you shut the car off, sounds like your getting some water collecting in your pipes. From sitting, it picks up carbon soot from inside the pipes, and just blows out on startup.

Really nothing to worry about. Only issue could be excessive carbon which would indicate a rich condition.

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Old Jan 13, 2007 | 08:11 PM
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My 2002 Z06 does the same thing! Carbon build up in the exhaust getting spit out with water vapor when you first start it up. Don't sweat it.
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Makes For Some NIce Black Spots On The Garage Wall! I Got Em!!
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