So when I use the vertex manipulation tool, a face of a block has missing textures, and when I test the map that face and that face alone is transparent. This is a car model made up of several blocks and my second attempt at using the vertex tool.
Though opposite faces of the block should be identical, one side is missing a texture like I said and the other doesn't. Also, when I move the block slightly to the side it works normally while when it is in place among the other parts it is still missing a texture.