This can't be normal - Help !!
Thread Starter
Pro
Joined: Dec 2003
Posts: 706
Likes: 46
From: Vienna VA
This can't be normal - Help !!
Ever since I did my H/C package I noticed that my exhaust pipes get covered with some black residue whenever I take it for a ride. I never knew how much residue was coming out till I backed the car in the garage and then started her up one morning. This can’t be normal, can it? Should I be concerned? Is there anything I can do to minimize this? FYI, the residue seems to be more carbon like than oil like, and I don't seem to be burning oil.
Melting Slicks
Joined: Oct 2004
Posts: 3,066
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St. Jude Donor '06
Is there any smoke? I'm thinking you are running very rich. I did a H/C over the summer, but I don't have anywhere near that much residue.
Someone more knowledgable will chime in, good luck
Someone more knowledgable will chime in, good luck
Racer
Joined: Apr 2005
Posts: 475
Likes: 1
Same Issue Here
My car has done the exact same thing since DTE did the H/C package on a my new LS2. I put a catch can on it and that cought some oil but the problem seems to be under high HP applications there is PCV blow by where oil froth gets into the intake. Take your intake off and I promise there will be oil in it. I run 442 RWHP and 440 RWTQ and I now have 12K hard miles on it and it runs great, I just have to clean the back of the car alot. There are many post on this and apparently this is a design defect of the small block. Run a query on "catch can" and you will see a pleathra of discussion on this topic.
Thread Starter
Pro
Joined: Dec 2003
Posts: 706
Likes: 46
From: Vienna VA
Does anyone know if oil in the intake is harmful, or is this just the nature of the beast and I'll have to live with it? What I have read about catch cans seems that they only catch 'some' of the oil. Are they even worth it?
Le Mans Master
Joined: Nov 2006
Posts: 7,215
Likes: 1
From: Orlando FL
Have you had a good tune put in the car? It looks like a rich condition is causing soot build up and the moisture brings it out the pipes. The reason you didnt see it before is you are moving a lot more air now. A catch can is a good idea but I would look into a quality tune. And yes there is a huge difference in tuners. There are much fewer quality guys than you might think. Good luck
Melting Slicks
Joined: Mar 2005
Posts: 3,222
Likes: 0
From: Mayfield kentucky
Have you had a good tune put in the car? It looks like a rich condition is causing soot build up and the moisture brings it out the pipes. The reason you didnt see it before is you are moving a lot more air now. A catch can is a good idea but I would look into a quality tune. And yes there is a huge difference in tuners. There are much fewer quality guys than you might think. Good luck
I had LGM tune my car and I still have a little soot.
Thread Starter
Pro
Joined: Dec 2003
Posts: 706
Likes: 46
From: Vienna VA
Have you had a good tune put in the car? It looks like a rich condition is causing soot build up and the moisture brings it out the pipes. The reason you didnt see it before is you are moving a lot more air now. A catch can is a good idea but I would look into a quality tune. And yes there is a huge difference in tuners. There are much fewer quality guys than you might think. Good luck
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Pro
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From: Gilbert AZ
Drifting
Joined: Jan 2004
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From: Orlando FL
Cruise-In VI Veteran
guys... its exhaust, its going to be black and sooty. you cant judge a car being rich because of that. when moisture builds up in the exhaust it mixes with the soot and blows out the tail pipes when the car is started!
no big deal
no big deal
Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
There are different aspects of tuning. You can tune a car for POWER and if you don't go back and adjust the LTFT's for normal everyday driving it can run RICH or LEAN under normal cruising conditions. Adjusting the LTFT isn't something your going to nail down on one tuning test drive. You may get lucky and get close. Most shops cant invest the time necessary to fine tune them so that there very close to perfect. I have spent hours and hours TWEAKING my MAF with EFI Live and I have it very close to where it needs to be. My exhaust tips use to be nasty black and sooty. Last weekend I scrubbed them out and I checked them this morning. They are still clean with only a little brown residue inside them!
BC
BC
Thread Starter
Pro
Joined: Dec 2003
Posts: 706
Likes: 46
From: Vienna VA
Thanks for all the replies guys. Much appreciated. Sounds like nothing to worry about. It's a beautiful day here in Virginia (nearly 60 degrees). I'm going for a ride to blow out some more soot...
Le Mans Master
Joined: Oct 2004
Posts: 9,369
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From: Zephyrhills, Florida
St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13
Race Director
Joined: Jan 2006
Posts: 10,554
Likes: 33
From: Not on either liberal coast.
When the weather warms up in the spring and you have an opportunity to drive the car for longer distances rather than just short trips or idling, you'll notice much of the carbon spotting will disappear. It's normal and more noticeable during the colder months.
Last edited by hotwheels57; Dec 17, 2006 at 04:19 PM.
Burning Brakes
Joined: Oct 2003
Posts: 1,106
Likes: 1
From: Foresters Falls(near Ottawa) Ont
My stock 2001 does just that. I've always considered it normal, I mean, 30mpg cruising at 70mph, things can't be too rich ...
RonJ ...
Racer
Joined: Apr 2005
Posts: 475
Likes: 1
After the car has been run for a while would the soot burn off? I was all over the "rich" issue but surmised no given the performance and very good MPG. I have confirmed oil in intake and many have confirmed this on the site. Could oil in the intake cause this affect?
Pro
Joined: Dec 2004
Posts: 563
Likes: 1
From: Mission Viejo CA
To start with the problem you discribed is all tune related. Your running pig rich from what I see. Not uncommon after the H/C install. If you scan the car you will see that your L-Trims are probably way off. Get a tune and have them bias it just a tad lean and your problem will be fixed. If you were in So Cal I could fix it for you in about an hour or so.
Last edited by Honez; Dec 21, 2006 at 06:35 PM.
Race Director
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12
Considering ECS did all the work you dont have to worry about tuning at all. I would call ECS and ask them if you could pour some GM Top End Cleaner over night and blow it in the morning.