I was taking my stock air intake off my car to install the Injen and noticed dark oily soot in the throttle body and one of the vacume hoses. Its very carmelized but I'm sure some made it into the engine. The engine is still running a smooth as ever, actually better because of the Injen, but I'm worried. What might the problem be? That's if there is a problem. I can get very paranoid when I modify my car.