[s-cars] A4 back on the road

[TM]

$2700 later, the A4 is back on the road.

Short recap:

'99.5 A4 1.8T

Coming off the highway, car seems to vibrate, thought I had a flat
tire, so I go to look for a safe place to stop. When I try to
accelerate,
the car does not want to accelerate at all, engine is obviously not
running correctly. So I pull over, know that the engine is not even
idling
correctly so I shut it off. No flat tire, purely an engine problem, at
this
point, I'm thinking I have a bad vacuum leak or bad coil pack causing a
poor running condition.

Have the car flatbedded to the local Bosch Service Center, find out that
the spark plug in cylinder 1 had disintegrated, electrode shot into the
cylinder, traveled from cylinder 1 to 2 to 3 to 4, found the electrode
in
cylinder 4. Plug was loose in cylinder 1, for whatever reason, maybe
that
started this whole process.

No codes except for the misfire from the disintegrated plug, no warning
of
this whatsoever. Pulling the head, the head around the exhaust valves of
1 and 4 were badly beat up by the electrode flying around inside, had to
have
the machine shop clean that area up, top of pistons 1 and 4 appeared to
be
shot-peened. Very minor damage in cylinders 2 and 3, fortunately. The
turbo
impeller got nicked, but didn't lose any blades, we'll see if the turbo
will
last.

Any suggestions on how to prevent something like this from happening
again?
I'll need to consult my tuner for any engine management issues- running
lean,
running the injectors maxed without any leeway for error, too aggressive
timing,
etc. We're running 93 octane on the east coast, so at least I don't have
to worry
as much about low octane gas. If the turbo is toast, I'll be going to a
K04 with
larger injectors and new software, unless there is a similarly priced
low budget
alternative.

Taka