Hi, I have failed emissions and I managed to notice, just today, that my exhuast is spewing black stuff on the ground upon start up. I guess it only does it sometimes cuz there are only two spots (one big one, one smaller) from all the numerous starts that it had in that spot. It usually happens on start up (what I've noticed) and it will toss this black stuff to the ground.
Here is the pic of it.

What does this mean???

I am thinking that it could be rich exhaust (but plugs don't show it), or it could be that my cat is done!

I just need some insight on this since no other car of mine had this problem.

P.S. I have a whole exhaust system with almost new cat 3inch waiting for the car. I guess now is the time to replace it!?!?!

 

dont know what that is but that looks like something that my parents school buses do when they first start up, but they are diesel

 

Looks like you're running rich. Also, everyone exhaust has black suet in it. If your letting your car idle/warm up there, and there is condensation coming out of your exhaust, that would do it also.

 

yea if you failed emissions, your more than likely running rich, and you've probably been running this way for a while now. All that extra carbon builds up in the exhaust, most of the time in the cat and muffler, and then when you fire it up its blowing out onto the cement..

either that or you have a CAT diesel under the hood!!

 

either that or you have a CAT diesel under the hood!! ??? i dont think anybody else gets it

 

i'll speel it out for ya....

Diesel Motor - an internal-combustion engine that burns heavy oil (diesel fuel)

CAT - A brand specializing in diesel equipment such as commercial, heavy duty equipment, marine use, etc. Infamous for heavy black suety exhaust.

black stuff on the pavement could be caused by the heavy black suet that a CAT diesel produces...

get my drift?

 

Check your cat. I had a van that did that once. Except much, much, MUCH larger black circles. I painted my dad's car with that exhaust. He never noticed the large starburst of black soot on his car. It gave it character.

 

My car does the same exact thing

 

i just put my cam and headers on and everytime i start my car up black sut comes out my pipes and i know i am running very rich(7MPG rich) so i bet you are as well.

 

As a side note, my new motor did that until the choke was adjusted properly.

JamesC