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Gook By Tailpipe


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Jan 17, 2002
Bourbon St. Balcony
Anyone look at their cladding near the tailpipe and notice black soot sticking?

It is driving me nuts...plus it is a pain to clean.

I wish the tail pipe was extended a bit more.

Am I alone with this problem???
I don't have this problem. Did your Av have the PCV/Lifter issue with burning oil? Soot and gook out of the tailpipe if I remember my pre-fuel injection days means an engine out of tune - I'm sure more mechanically inclined Av owners will jump in - I'm starting to feel like I'm all thumbs reading the threads here and the absolute wealth of knowledge that folks have on the Av!!!

I do not have any oil burning or smoke issues it just seems to be splotches or dots of carbon.
ygmn said:
I do not have any oil burning or smoke issues it just seems to be splotches or dots of carbon.
After a long drive (this is a key point), let it sit overnight then have someone watch the tailpipe when you start it the next morning.
I have looked when someone else starts it. The exhaust tip is black like it is running rich but no oily residue just a carbon black type specs. Very small and very annoying as I am a neat freak!!
:)I have no carbon build up on mine since october. The black soot specs on my truck was from the black tire dressing the dealership used!
Check the other side also. It is very possible that what you are seeing is either tire dressing, or road tar thrown up by the wheels. I cant think of anything that would come out of the tailpipe that would give you small specs, it would be more likely to be a large area of discoloration.
Only on Tail pipe side as I washed it yesterday and inspected again. I thought it was tar at first but it is only on one side and seems to be lessening as I inspect before each wash.

It is not tire dressing as none of the other wheels have it and I use the same PDMS type protectant on all the tires.

I swear it looks like carbon. ???
You should have seen the picture I brought to my arbitration hearing. The oily, sooty black stuff was running down my driveway while the Z-71 AV sat there warming up. This vehicle was repurchased by GM at over $35,000 due to the oil/smoke problem they couldn't fix.
I have just started noticing black spots on the rear bumper/ backstep. I also noticed that the inside of the tailpipe in now black. I haven't seen any oil consumtion, and the info center never reads a problem from the E.C.M. I was thinking about disconecting the negative terminal like when I installed the FIPK. Maybe the E.C.M. needs to reset. I figured the computer would pick up on any problem like running rich.