My 2007 Honda Accord is making a loud knocking noise in the engine when idling and driving. It started a few weeks ago and it getting louder. It hasn't affected the way it drives yet, but I am not sure what is causing the problem. A few months ago, I paid $600 to have a mechanic find a small oil leak. Although, he said it was fixed, it is still leaking. It is just a few drops at a time, but I can smell the oil leak after I have driven a few miles.

2007 Honda Accord with 139,000 miles.