Originally Posted by Dajerseyrat
I just cleaned my carb a few months ago cause the car sat for a while. I recently found this muddy grey substance in my carb..The fuel was Sunoco 100 octane and was in the tank for about 1 month. What do you think the cause of this is? I'm gonna remove the fuel cell and flush the whole system now..I'm assuming its something in my fuel cell causing it...
Looks like you got fuel contaminated with a plastic monomer like styrene. This happens more than one would like to see, filters will not pick this up if this is what it is. You need to get this checked out as uncured plastics dissolved in gasoline can wreck the inside of the engine by gluing the rings into their lands.
When I lived in Houston many years ago this happened with Diamond Shamrock, they got fuel contaminated with styrene monomer while in pipeline transit. It ruined a great many engines in the Houston area. Goes to show you how much they don't test what they deliver to gas stations.