when i but ethanol 10% fuel in my car it blows out black smoke when i step on it what is causing this?

Question

I use 93 octena becouse i have a camaro z28

Answer 1

If you have a 350, you're wasting your money on 93. Use what the manual says.
No way 10% moonshine should be causing black smoke unless something else is wrong. Maybe a bad O2 sensor.

Answer 2

The black smoke means it is running to rich, to much gas. the O2sensor can make it do this.
But I think that 93 is a little to high.
Switch to a mid grade for a few tanks and it should clear up this problum

Answer 3

try a tune up and some lucas fuel injector cleaner