I had a recent code pop up on our voyager, lean on bank 2 or something if I recall correctly. Tried all the suggestions here, clean maf sensor etc. On the net was a TSB about a valve cover that should be replaced with a new valve cover because of a design change. I wasn’t about to do that without verification so off to ford we go. They replaced a plenum gasket and a couple of other things. I asked about my ability to troubleshoot that problem and was told that their machines read more codes and info than the generic ones at the parts store. Do I believe them, I guess I have to as the cel problem was solved.