Ok I just went to take off my upper intake plentum and I noticed not so much inside the plentum but all inside the lower intake runners this black sh*t. It almost looks like road grimme. It is black sort of wet and feels almost like dirt or shredded rubber when rubbed between my fingers. Does anyone have an idea what this could be or if i should be really worried ?

 

My guess is a carbon buildup from unburned fuel. (running rich) I'm guess if the Zs running somewhat rich from factory it would be normal but I'd clean it off of course.

I guess I need to check mine out, 77.3k miles... I can only imagine what mine will look like

 

Yea my car has been running quiet rich, hopefully this is carbon build up, but it seems too think to build up unless i just have that much ?

 

How many miles?

I took my throttle body off about 10k miles ago and cleaned it because of the buildup on it. I need to do the same for the lower collector I'm sure.

 

about 9k miles since motor was built.

 

Get an oil catch can.

 

Yes I also noticed a small puddle of oil in the intake, so catch can a must !!