Look at the exhaust pipe -- if it is liberally coated with soot inside and has a ring of fresh soot on the outside, you are definitely running rich.
Oh yes, there is black soot inside, and that infamous black ring around my exhaust.
Another thing to add; I use "Quaker State Higher Mileage" Oil 10w-30, is that oil too thin??
should I use 10w-40 or 20w-50??
I dont want to start another oil thread.
1987 mercedes 300E
1995 e320 conversion(hated the 300e grill)
Monochromatic Paint (Custom Blue)
Flat Badged (front)
custom "carbon fiber" console
18 inch HP EVO rims
Sold! Now I drive a Monte Carlo SS