Sounds like it's coming from the tensioner rail area. Just pulled it apart to check VVT system and chain tension was good. Throwing cam sensor codes. Should I be worried about this?
I haven't actually. I drove it until March of 2016 when my transmission blew up on the highway. I'm going to be swapping in a TDI and manual transmission when my Mercedes is all buttoned up. I highly recommend the swap instead of replacing the chains. It'll boost the value of your van and it's almost guaranteed that the automatic transmission will give up at some point.