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How I holed my piston...



All,
	Dave was curious about how I holed my piston,
so here I go...

	The year was 1990, and I'd owned my SVO for over
3 years.  Occasionally, from the very first week I'd owned
it, it would suddenly start running like crap, usually when
I'd been driving it continuously for a long period of time.
I was in the army, and only road tripped about twice a year,
and it never actually stranded me.  I had the computer 
checked, but no codes ever showed up.  It bugged the crap
out of me, but the dealer said there was nothing they could
do if I couldn't make it do it at the shop.
	It started happening a little more often, sometimes
after only about half an hour of driving, but sometimes it
would still go for months without doing it.  I thought my
fuel pump(s) were going out, and replaced them and changed
my filter...no change.  There didn't seem to be anything I
could do, so I just drove it that way...
	One night is was coming up I24 from Nashville towards
Clarksville, TN, and some guy in a late model (at the time)
GM with a quad 4 started messing with me.  I floored it, and
it started to run like crap (missing and bucking...sometimes
if you let off the gas and floored it, it would go away).  I
was so pissed off I just stayed on it and figured, "Well, if
anything goes wrong, at least I'll know what caused it".
Famouse last words...about 30 seconds later (the car was still
running poorly, and I still had it to the floor ;-)), there was
a loud pop, and I laid the biggest smoke screen you ever saw.
I'd holed a piston (I think the TFI was sending out sparks to
some of the cylinders randomly).  When you hole a piston under
boost, you instantly pressurize your crankcase and blow out
your gaskets...and my PC valve was blown out of it's hose, too.
This blew oil all over the motor that made the first part of
the smoke.  Then, as soon as you let off the gas, crankcase
oil gets sucked into that cylinder and blown out the exhaust
pipe.  The only way to stop the smoking was to run at exactly
neutral throttle.  Anway, I drive it the 10 miles to my house,
and ended up buying a remanufactured short block, and having
my head and turbo rebuilt.  Oh, if only I'd known then what I
know now ;-).  Man I could build a great motor for what I
paid for a stock one :-(.
	The bad thing was I still didn't know it was the TFI
causing my problem.  I finally figured that out when it totally
quit shortly thereafter, and I haven't had the problem since.

It's a story of youth and stupidity...but it's handy to know.

Moral:  If your EFI Ford runs like crap only when the motor is
warm, but doesn't set any computer codes, always suspect the
TFI module...

-- 
Carl_Morris@StorTek.Com