Every so often after my 1989 Vanagon GL has sit for about a day or two
without driving I hear an odd tapping coming from the engine. It does not go
away while sitting at idle.

However, after driving a few minutes it goes away and does not appear again
unless I let the van sit for two days or more.

Any advice or comment? Should I be concerned?

William
1989 Vanagon GL
1988 Mercedes 300SE