discharge from exhaust?

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Wed 27 Aug 2003 01:21
discharge from exhaust? - steve_rt
I have often wondered if someone could explain this to me - what can you tell about the state of a car from the liquid that comes out of a car exhaust? is it simply condensation or is it possible that it might be fuel of some sort?
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Wed 27 Aug 2003 07:09
discharge from exhaust? - DL
Simple one Steve - Water is a by-product of fossil fuel combustion, it emanates out of the exhaust pipe as steam or condensate, depending upon exhaust temperature.

There are no set limits as to how much or little water coming out of the tailpipe is good or bad so no conclusions as to the state of the engine can be drawn from it.

This stuff is the main cause of exhuast system corrosion, from the inside out....not the other way around as is commonly believed.
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Thu 28 Aug 2003 21:50
discharge from exhaust? - Adam Going (Tune-Up)
Spot on DL. And as Catalytic Converters produce more water than ordinary combustion, that is why modern exhaust systems (from the Cat back) rust out sooner (when car is used for short trips) than non-Cat cars. Another reason for all modern cars requiring a decent run once in a while (week !). In my view stainless steel systems should have become law along with Cats, but we can all dream !

On the other hand EXCESSIVE water emissions, accompanied by constant coolant loss, could be a sign of a head gasket problem.

Regards, Adam
Whatever is rightly done, however humble, is noble.
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Fri 29 Aug 2003 08:36
discharge from exhaust? - Cliff Pope
I think if the steam on a cold morning effect persists then it shows that the engine isn't warming up properly. It could indicate something else amiss - when the duct to my AMM came off I first noticed constant steam from a normally colourless exhaust.
You can also do a useful diagnosis by running your finger inside the tail pipe. It should be absolutely clean and sootless.
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