Hello, all.

This car has 130k, and has run well for me since I got it early this
year.  It suddenly began a dead miss on all cyl, like a backfire.  I
have changed out the gas filter, it has recent plugs/wires/rotor/cap.
An earlier complaint was that it pinged intermittently, but usually ran
strong.  However, the miss is getting worse, but often doesn't show up
until it has been run for a while.  The car also has had a recent O2
sensor replacement.  This one has TBI.  I suspect an air leak
somewhere, but am open to input from wiser heads.