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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.
I agree and do notice some minor carbon deposits on the outer pipes routinely, but never on the paint like the OP describes. He says he sees smoke, presumably black, coming from the exhaust at times, and that isn't something I've ever seen with either of the two C7s I've owned. I suspect it is a combination of condensation (water) that forms in the exhaust when cold combined with a rich mixture from the 60-sec. dual-pulse process. This along with an overzealous right foot when the car is cold might create these spots.
I have gotten this from day one on my Yellow car. My Yellow 2000 coupe did the exact same thing. You have to get close to see it. The explanation I saw that made sense is that the back of our cars is a low pressure area and the exhaust will swirl up in that area.
2016 C7 Stingray.
2800 miles.
I visited 3 dealerships and they cannot find the way to fix it. Does anyone has the same problem?
I think the car is lemon.
The spots are covered all over my trunk. I tried different gas stations .Checked the oil. Nothing. My son is kind of mechanic and he thinks there is a serious issue. I am tired of cleaning the back of the car and I am afraid it will be more issues after the warranty.
Does anyone has any idea how to fix that or shall I continue talking with GM ?Please advise.
Looks like newly paved road tar !!! Use the " Tub of Towels " product !!! I use these towels especially in the wheel wells and underneath both the front end and rear end of the car !!! Wayne
I get this as well, and did from my C6. C7 seems to get more. I spoke with a tech at the dealership and they said grey tips car is running too lean. Black tips and engine is fine, some say on the 'rich' side. All newer cars are like this, just observe exhaust outlets or tail pipe on any newer car. Not a problem. Except to keep clean
Looks like newly paved road tar !!! Use the " Tub of Towels " product !!! I use these towels especially in the wheel wells and underneath both the front end and rear end of the car !!! Wayne
It's environmental VOG!
The engine is working fine.
All the theories here seem to blame the car or the road as the source of the spots, but there is another possibility. There is a fungus that thrives in garden mulch, and it reproduces by launching sticky spores into the air toward the sun (or a light colored object that reflects the sun, like a car). The spores stick like glue to your car, and they are nearly impossible to wash off. I had this issue with a previous car which I parked at work by a mulch planting bed. If you think I'm making this up, Google "Artillery fungus" and check it out.
My 2016 ZO6 has the normal signs of richness, outer tips get dirty fast.
I had NO NOTICEABLE oil spots before, this, 0-4000miles.
But 2 weeks ago I caught the dipstick down a whole quart. So I added it and retested and put it smack in the middle of the marks. Yes I know how to check the oil.
Since then its been spitting black stuff, its not dry, its oil and a finger can smear it off. So I can attest, from my experience, I must have overfilled the oil. I cant believe it. Power is down too. How can that oil make it past a hot cat. How does it get in there? Past my valves? NOooooooo...
Now how to I extract 1/2 quart without pulling the plug?.
Its not normal, I didn't have it before. NEVER ONE SPEC. Silver Car.
Its not cool, to have oil get through there.
Its not tolerable, for this or any other auto to spit oil like this.
Stay tuned.
My 2016 ZO6 has the normal signs of richness, outer tips get dirty fast.
I had NO NOTICEABLE oil spots before, this, 0-4000miles.
But 2 weeks ago I caught the dipstick down a whole quart. So I added it and retested and put it smack in the middle of the marks. Yes I know how to check the oil.
Since then its been spitting black stuff, its not dry, its oil and a finger can smear it off. So I can attest, from my experience, I must have overfilled the oil. I cant believe it. Power is down too. How can that oil make it past a hot cat. How does it get in there? Past my valves? NOooooooo...
Now how to I extract 1/2 quart without pulling the plug?.
Its not normal, I didn't have it before. NEVER ONE SPEC. Silver Car.
Its not cool, to have oil get through there.
Its not tolerable, for this or any other auto to spit oil like this.
Stay tuned.
Yes indeed, not normal, its has to be a oil leak of some sort. Just open the drain plug and knock out a 1/2 - 3/4 of a quart. Easy to do.
My 2016 ZO6 has the normal signs of richness, outer tips get dirty fast.
I had NO NOTICEABLE oil spots before, this, 0-4000miles.
But 2 weeks ago I caught the dipstick down a whole quart. So I added it and retested and put it smack in the middle of the marks. Yes I know how to check the oil.
Since then its been spitting black stuff, its not dry, its oil and a finger can smear it off. So I can attest, from my experience, I must have overfilled the oil. I cant believe it. Power is down too. How can that oil make it past a hot cat. How does it get in there? Past my valves? NOooooooo...
Now how to I extract 1/2 quart without pulling the plug?.
Its not normal, I didn't have it before. NEVER ONE SPEC. Silver Car.
Its not cool, to have oil get through there.
Its not tolerable, for this or any other auto to spit oil like this.
Stay tuned.
A couple of things:
I agree that some members were a little rough on the OP, but in fairness, the OP was a little dramatic in his stating of the problem.
The OP stated that the spots were carbon, not oil.
If you "know" how to check your oil, how did you overfill?
As to how to remove oil without resorting to the drain plug, how about a turkey baster and suck it out of the dry sump reservoir?
2016 C7 Stingray.
2800 miles.
I visited 3 dealerships and they cannot find the way to fix it. Does anyone has the same problem?
I think the car is lemon.
The spots are covered all over my trunk. I tried different gas stations .Checked the oil. Nothing. My son is kind of mechanic and he thinks there is a serious issue. I am tired of cleaning the back of the car and I am afraid it will be more issues after the warranty.
Does anyone has any idea how to fix that or shall I continue talking with GM ?Please advise.
2019 z06
401 miles
Same here I wash my CMG z06 every sat or Sunday by Friday the rear looks like oreo ice cream... doesn't stop me from enjoying the car as it's my DD! sadly don't have a solution to prevent the problem other than not driving it, I just clean it and move on just throwing it out there I feel your pain.
2019 z06
401 miles
Same here I wash my CMG z06 every sat or Sunday by Friday the rear looks like oreo ice cream... doesn't stop me from enjoying the car as it's my DD! sadly don't have a solution to prevent the problem other than not driving it, I just clean it and move on just throwing it out there I feel your pain.
The OP and you should include a picture of your exhaust tips, are they black and sootie also ??
I'm at work right now but I'll add a picture later on, yes I never clean my exhaust tips I actually like that they're black weird I know.
thank you
My point was if they are real black and really sootie, try and clean them up. Wipe clean as far in as you can reach all the way out to the edges and see if you still get the spots (after you clean the spots off the rear bumper cover first). Check it after a few 25 mile drives
05-22-2017, 10:15 AM
