LT1 with LT4 hotcam - problem
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Pro
Joined: Apr 2000
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From: Clarkston Mi
LT1 with LT4 hotcam - problem
Got an issue that I have posted in the past with little responce, so I will try again, before I buy parts and start a repair.
Car has not been started since December. In storage (garage) with full tank. Going to start her soon, go out - cant wait.
Last season, I noticed that I have black residue 'trickling' out of the tailpipes. Smells like unburned - or partialy burned fuel. Only at idle, it is not burned oil.
I have not reprogrammed the computer since I dropped the new engine in.
I am thinking that I have a cracked injector. I want to get your opinions before investing in a new set of injectors. BTW; it did not do this until nearly a year after the engine is broken in.
Car has not been started since December. In storage (garage) with full tank. Going to start her soon, go out - cant wait.
Last season, I noticed that I have black residue 'trickling' out of the tailpipes. Smells like unburned - or partialy burned fuel. Only at idle, it is not burned oil.
I have not reprogrammed the computer since I dropped the new engine in.
I am thinking that I have a cracked injector. I want to get your opinions before investing in a new set of injectors. BTW; it did not do this until nearly a year after the engine is broken in.
Race Director
Joined: May 2001
Posts: 14,165
Likes: 9
Water is a normal byproduct of the combustion process. At idle your exhaust is likely moving so slow that the water vapor has time to codense and then "drip" out of the tailpipe. It is black because it picks up the carbon from within the pipes. It may smell somewhat like fuel because there will be some amount of unburned fuel due to the overlap in the cam.
In short what I'm saying is that it's perfectly normal, don't worry about it. Pay attention to the cars around you at traffic lights and you'll notice that water may drip slowly out of the exhaust pipes and may pour out for a brief instant when they start to move again if they've been sitting for any length of time.
In short what I'm saying is that it's perfectly normal, don't worry about it. Pay attention to the cars around you at traffic lights and you'll notice that water may drip slowly out of the exhaust pipes and may pour out for a brief instant when they start to move again if they've been sitting for any length of time.
Thread Starter
Pro
Joined: Apr 2000
Posts: 621
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From: Clarkston Mi
Yeah - I know that some condensation is the norm, and I can agree with a little bit of 'drip' action...
But, if I leave my car running in the drive, to warm up (10-20 minutes...) it will leave two black 'patches' on the driveway from this drip action. Seems a little more than the norm, perhaps a little concerned.
But, if I leave my car running in the drive, to warm up (10-20 minutes...) it will leave two black 'patches' on the driveway from this drip action. Seems a little more than the norm, perhaps a little concerned.
Team Owner
Joined: Oct 2004
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
Could be an O2 sensor. The readings can be skewed, but still in the range of not throwing a code, even if just barely. May be time anyway just as a course of maintenance. I find they are good for 80K safely, usually by 100K they're shot.
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
Originally Posted by jsup
Could be an O2 sensor. The readings can be skewed, but still in the range of not throwing a code, even if just barely. May be time anyway just as a course of maintenance. I find they are good for 80K safely, usually by 100K they're shot.
Yes, they can be "lazy" and slow to respond and still not log any codes. 
Le Mans Master
Joined: Feb 1999
Posts: 6,172
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From: somers, ny
I think i'm with Nathan on this one. Particularly in cooler weather, mine will drip quite a bit and anything that comes within 10 feet of my exhaust smells like unburnt fuel....including clothes, rodents, small children, etc.
Safety Car
Joined: Feb 2000
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From: Howell N.J. Home of Redgar
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Originally Posted by Nathan Plemons
Water is a normal byproduct of the combustion process. At idle your exhaust is likely moving so slow that the water vapor has time to codense and then "drip" out of the tailpipe. It is black because it picks up the carbon from within the pipes. It may smell somewhat like fuel because there will be some amount of unburned fuel due to the overlap in the cam.
In short what I'm saying is that it's perfectly normal, don't worry about it. Pay attention to the cars around you at traffic lights and you'll notice that water may drip slowly out of the exhaust pipes and may pour out for a brief instant when they start to move again if they've been sitting for any length of time.
In short what I'm saying is that it's perfectly normal, don't worry about it. Pay attention to the cars around you at traffic lights and you'll notice that water may drip slowly out of the exhaust pipes and may pour out for a brief instant when they start to move again if they've been sitting for any length of time.
...Mine does the same on the garage floor ....no biggie car runs like a champ !
