I own a 1998 Subaru Legacy wagon with the 2.2 liter motor, automatic.
Recently I noticed a slight engine knock/tap sound mainly first 10 minutes
of driving when driving aound town. Not major loud at all but you can here
it up front slightly. Disappears after car warms up. I read somewhere this
is a common issue for this model and may not effect engine wear. It has
136,000 troublefree miles on it.  Any information appreciated and if others
have this issue.