What causes your motor to make a loud popping noise? Still starts?

What is your question?

This is the HEMI. I have been having the same issues with the water leaking down and causing the sputtering. Yesterday after driving my car to work and lunch with no problems till after work. It started and I got about 2blks when I heard a popping sound. I thought my tire had blown and was slapping against it. It is very loud, and is coming from under the hood. I restarted it and it starts, idles poor and that sound is still there? It has oil in it and is well kept. SO... do did I throw a ROD? Could it be a easy fix?