It's been awhile since I worked on my car but I know I lost an exhaust manifold bolt, since I've been driving without it I've been getting smoke and what sounds like an exhaust leak.

By not putting this bolt in I believe there are two others that are in, did I screw something else up? At the time I didn't think it was a big deal to not put it in and I would go by the dealer and pick up a new bolt, but now Im thinking something else is messed up I also am getting a CEL now and a very rough idle sometimes.