Well, I did get the driver side valve cover off and no signs of a problem. It must be on the other side. I was pretty stupid and never thought to scan the codes. Can you do it with the engine off? I did crank it up to see if I could hear which side the noise was coming from and it started making more bad noises so I turned it off. How do yo get the fuel line off right above the driver side cover. I have a 3/8 tool that I used on my 06 Cummings fuel line and it popped right off. This one does not seem to work. Do I have the wrong size or kind? Mine has a square shoulder and does not want to go very far inside the fitting. Seems like it needs to be more of a taper.