Backfire. The answer

["Steve Bradley" <scscomp@mindspring.com>]

And the answer is, you are all correct.

I worked as a VW mechanic for 9 years and have replaced plenty of mufflers
in all types (bad pun) of VW's.

I've replaced leaking mufflers on VW's that backfired and replaced leaking
mufflers on cars that did not backfire.

9 times out of 10, a new muffler would stop the backfiring on cars that
backfired previously. I don't know why, it just did.

It is apparent that a new muffler somehow does mask the underlying problem,
lean mixture, bad timing, whatever.

You all can flame me, disagree with me, doesnt't matter. These are the
facts.

Steve B.