I missed the beginning of this thread, but still can't understand how
pistons are burning if your only getting 16mpg.  It can't be a lean running
condition.  Is ignition timing advanced too much?

My wife and I have been on the road in our '82 air-cooled 2-liter
fuel-injected Vanagon for a while now; since my last post, we've
driven from Kansas to Ohio, then back to New Mexico, then up to Omaha,
where we burned a hole through one of our pistons.  Cram Foreign Auto
Parts on 72nd Street, staffed entirely with Volkswagen enthusiasts,
has been very helpful in getting stuff fixed, and they contract out
the engine rebuild work to a guy named John.

*snip*
It's still noisy, gets 16mpg, has stinky exhaust, has a broken heater,
leaks gasoline from the top of the tank (I think a new breather hose
set would solve this, but I don't know where to get one on the road),
doesn't have a working odometer, and has the battery isolator hooked
up wrong.

*snip*
John, the engine rebuilding guy, called to say that we were very
lucky; we hadn't spoiled the heads, but we'd burned through one piston
and a second one was just about to go.  I'm glad it wasn't the valves.