Thanks for the quick reply. I suspect multiple issues as well, particulaly for the misfiring. Bosch platinum plugs looked OK -- no carbon tracking (mechanic who pulled the codes said to look for that), good gap measure, and white or grey color with a tinge of brown in places.
I have not worked on the engine myself except for simple things like plugs & wires, filters, etc. The sound really seems to be inside the cam gear housing -- I'll confirm this evening with another listen.
If it's the cam gears/timing chain, I guess that means replacement of all that, right?
Thanks,
