1998 base Lumina. has about 280,000. miles on it now.
original engine.
tranny rebuilt around 175,000 miles.
head scratching nowadays=
1) vacuum leak causing a/c to default to defrost mode.
and
2) a very small coolant leak, passenger side , drops on back side corner of engine block , nearest to firewall. leak location unknown.
possibly coming from timing chain cover area ???