I have a stock d16a6 and have from the cat 2.5" exhaust to a ebay muffler. Sounds asome and no fart can sound but my question is i get alot of block dots on the back of my car from the exhuast. Could that be because of it being to big should i go smaller?

 

ttt

 

Oil Residue. Your probably lightly burning some oil.

 

my 88 si did was burrning a lot of oil and i had a lot of black crap all over the rear bumper then i bought a b16 and fixed the problem, after i blew up the d16

 

You're muffler bearings are worn out.

 

my wa? muffler bearings are you on crack?

but would smaller exhaust help?

 

black spots? Does it look like its carbon mixed with water?

I have the same problem. But, I know I am having some fuel/air ratio problem with my engine.

Could be fuel injectors, could be not enough air coming in. If it was oil burning, you would be seeing white everywhere or at least some smell of burnt oil.

 

all cars do that...unless its excessive...then u are running too rich