I have read the rules of image content etc, and for the life of me I do not understand how my image "pure power" was rejected, an image of the car was allowed but a picture of the engine was not!
Just guessing here, but was the brand name (Benz, Fiat, etc) prominently displayed? If so, maybe it was rejected for copyright/brand reasons. Again, a guess because it's the only reason that I can see fitting.