Back of my car is covered with black spots
Thread Starter
7th Gear
Joined: Nov 2016
Posts: 7
Likes: 1
Stop using lousy language
Lol your car is not a lemon... if your driving with the exhaust on sport of track mode it lets out a lot more soot then when driving in tour mode because the flaps are open. Get a damp rag clean it off and stop crying about it. If you really regret buying the car because of this issue sell it. I doubt GM will take it back because you are to lazy to clean it once in a while lol.
Do not answer if you are productive !!!!~!!
Thread Starter
7th Gear
Joined: Nov 2016
Posts: 7
Likes: 1
Best answer!
Thanks!
Le Mans Master
Joined: Dec 2008
Posts: 6,612
Likes: 493
From: brooklyn ny
I'm not trying to insult you at all actually... but if you think the car is a lemon because of a little exhaust soot you might just be a little on the dumb side that's all. What does your gtr have to do with this car or anything else? This isn't a gtr it's a corvette.
Call a lawyer and sue gm hahaha... I can't wait till they ask your for your testimony. "Your honor my car is getting dirty and they won't fix it"
Call a lawyer and sue gm hahaha... I can't wait till they ask your for your testimony. "Your honor my car is getting dirty and they won't fix it"
Last edited by Steve Garrett; Feb 2, 2017 at 10:10 PM. Reason: Merged Posts-please use the Multi-Quote button (middle icon) in the lower right hand corner of each post to make your response look like this.
Instructor
Joined: Jul 2005
Posts: 178
Likes: 58
From: Jersey Shore NJ
2021 C2 of the Year Finalist - Unmodified
"More than likely, especially this time of year, it's normal condensation that isn't getting burned off within the exhaust system. Look at cars in the winter time with water coming out the tail pipes. That's why exhaust systems rust. Many people don't drive their cars in the winter, they start them up and let them idle. The combustion process forms H20 in the exhaust, but the exhaust system doesn't get hot enough to burn it off. The condensation takes a little of the carbon out the tail pipes and that's probably what you're seeing. "
Last edited by Birdman63; Feb 3, 2017 at 02:36 PM.
Tech Contributor
Joined: Oct 1999
Posts: 41,058
Likes: 9,821
From: Charlotte, NC (formerly Endicott, NY)
If you use the throttle a lot you will see more spots than if you are taking it easy around town or driving on the highway.
As far as I am concerned it is a problem that you want to have as not having spots back there means the car isn't running hard.
Bill
Thread Starter
7th Gear
Joined: Nov 2016
Posts: 7
Likes: 1
I'm not trying to insult you at all actually... but if you think the car is a lemon because of a little exhaust soot you might just be a little on the dumb side that's all. What does your gtr have to do with this car or anything else? This isn't a gtr it's a corvette.
My son is a mechanic and we talked to people. Speedway Chevy in Monroe,WA manager said that this car is not fixable and he has never seen such thing. Whole trunk is covered with carbon deposits all over.
What is this becomes a serious issue after my Warranty is over? I don't even know what you have but I have never had this type of issue before in any of my cars and this is why I mentioned it. Thanks!
Saw This Maybe?
"More than likely, especially this time of year, it's normal condensation that isn't getting burned off within the exhaust system. Look at cars in the winter time with water coming out the tail pipes. That's why exhaust systems rust. Many people don't drive their cars in the winter, they start them up and let them idle. The combustion process forms H20 in the exhaust, but the exhaust system doesn't get hot enough to burn it off. The condensation takes a little of the carbon out the tail pipes and that's probably what you're seeing. "
"More than likely, especially this time of year, it's normal condensation that isn't getting burned off within the exhaust system. Look at cars in the winter time with water coming out the tail pipes. That's why exhaust systems rust. Many people don't drive their cars in the winter, they start them up and let them idle. The combustion process forms H20 in the exhaust, but the exhaust system doesn't get hot enough to burn it off. The condensation takes a little of the carbon out the tail pipes and that's probably what you're seeing. "
Last edited by Steve Garrett; Feb 2, 2017 at 10:10 PM. Reason: Merged Posts-please use the Multi-Quote button (middle icon) in the lower right hand corner of each post to make your response look like this.
Le Mans Master
Joined: Dec 2008
Posts: 6,612
Likes: 493
From: brooklyn ny
Also if your son is "kind of a mechanic" and thinks this is a serious issue you might want to point him in a different direction as far as a career.
Customer: "my Windshield wipers are leaving streaks on my windshileld"
Son: "that seems like a serious issue might be a lemon"
Customer: "my Windshield wipers are leaving streaks on my windshileld"
Son: "that seems like a serious issue might be a lemon"
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Safety Car
Joined: Dec 2007
Posts: 4,070
Likes: 162
From: Coralville Iowa
Looks like carbon / soot from a chronic rich fuel mixture. Definitely not normal - I also have a torch red C7 and see dust at times but nothing like that. What is your gas mileage - I suspect it's horrible based on the excess amount of fuel you are burning. "Black exhaust" unless you are absolutely hammering on it is also not normal. Interior of exhaust pipes should be black and filthy - also not normal.
Instructor
Joined: Sep 2016
Posts: 184
Likes: 59
Try driving in Eco or Tour if you have NPP and see if it does it as much or eliminates it entirely. If you have a heavy foot, especially this time of year and you live in cold climate, I'm thinking its just soot from the exhaust and condensation mixing. If it was running to rich, I think it would set a code and a light. May sound stupid, but have you rubbed any on your fingers and see what it smells like? Or maybe just check the consistency of it? If oil or diff fluid it will obviously be oily.
Instructor
Joined: Nov 2005
Posts: 159
Likes: 4
From: Riverview FL
I have them too. But it wipes right off. It was really bad until I got a really good tune. But I also have a cam, blower, headers and no cats. After a few good pulls on a dyno, it needs a cleaning. I have a matte pearl white vinyl wrap on the back so I just use some soft scrub (without bleach) and it all just disappears. It's worth the extra 200 hp. But it is WAY cleaner than it was after a good dyno tune. Also, there are a few products from Chemical Brothers that have worked wonders on the rear so now I can just wipe it off.
I agree to have a good tuner check it out and see if it is just running rich.
I agree to have a good tuner check it out and see if it is just running rich.
Le Mans Master
Joined: Dec 2014
Posts: 6,140
Likes: 2,745
From: Northeast
I get the dirty butt too on my AW. If it's between washes, a couple swipes by a California Duster does the trick.
It's a combination of soot and road grime kicked up by the tires. Lemon? No, just dirty IMO, and certainly nothing to lose any sleep over...
If you conduct a search you'll see that it's very common, particularly on lighter colors where the contrast is more visible.
It's a combination of soot and road grime kicked up by the tires. Lemon? No, just dirty IMO, and certainly nothing to lose any sleep over...
If you conduct a search you'll see that it's very common, particularly on lighter colors where the contrast is more visible.
Last edited by sTz; Feb 3, 2017 at 09:30 PM.
