No start... Start.... Knock when started.

What is your question?

Started vehicle took it to the gas station filled it up. Went to restart and nothing. No cranking over just auxilary power. Waited for 10min then started right up. While driving home I reached 55-60mph. Heard a faint winding up noise followed by a jerk. Imediatly after the check engine light came on. Did not test my luck at 55 mph or above the rest of the way home. Now when it starts it makes a clunk noise one time while the engine is firing up. Idols and runs fine but check engine light remains and exhaust is slightly cloudy. Any suggestions I am lost