[Shotimes] Intermittent Misfire on '94 w/ATX (long)

[Carl Prochilo]

Just curiious.  In any of that long list of work did you do a KOEO
or KOER test?
-- 
Cheers,
Carl Prochilo
1992 Ultra Red Crimson

J.B. Hebert said:
> Hello:
>
> I've been working on a problem with my '94 SHO 3.2 ATX.  It's
> driving me
> nuts, so I'm hoping that someone here can point me in the right
> direction.  It started a few months ago with a surging/misfire at
> light
> throttle input.  I thought I might have gotten some bad gas, so I
> ran a few
> containers of Techron through and the problem seemed to go away.
> Then a
> week or two later it came back again.  It felt like one or two
> cylinders
> were not firing properly.  Following standard troubleshooting for
> these
> cars, I first checked the spark plug wells.  Sure enough, 2 or 3
> were
> nearly full of oil, so I replaced all the valve cover seals and
> cleaned out
> the spark plug wells thoroughly.  After reassembling the car, the
> problem
> once again seemed to be resolved.  However, after a few hours of
> driving it
> returned.  At this point I had my mechanic run a few tests, and he
> found
> that one of the cylinders was running lean.  I decided to have the
> injectors rebuilt in case I had one intermittently sticking.  At the
> same
> time I replaced the coil, in case I had one that was failing, as
> well as
> the air and fuel filters.  I put the new injectors in, and once
> again
> everything was fine for a while.  Then the problem returned.  At
> this
> point, I thought it might be a spark issue.  Even though the
> previous owner
> had recently had the spark plugs and wires replaced, they did not
> use
> quality wires, so I replaced the spark plugs with the appropriate
> Motorcraft platinums and put a set of Taylor spiral core wires in.
> After
> doing this, the car ran great for about 15 minutes.  I took it out
> on the
> highway and got it warmed up, then did a couple hard acceleration
> runs.  It
> was running out smoothly and with good power.  However, after the
> second or
> third run, I noticed that the car wouldn't rev over about 3800 RPM.
> It was
> like it was hitting a rev limiter or something when it tried to open
> the
> secondary runners.  Suddenly, I completely lost power and the tach
> dropped
> to around 300RPM, even though the engine was still turning much
> faster than
> that.  I managed to get to the next off ramp and at this point the
> car was
> running on MAYBE two cylinders.  It would move, but the exhaust note
> was
> very bad and the transmission was having trouble shifting.  The tach
> was
> way off; it would read around 400 RPM even after a shift.  Around
> this time
> the cabin started to fill with nasty, burnt plastic smoke.  I pulled
> off to
> the side of the road and shut down.  I popped the hood and could not
> find
> the source of the smoke.  It soon disapated so I started the car,
> and it
> ran much better.  However, while limping home it got worse again and
> the
> smoke returned.  I made it home and shut the motor off, coasting
> down the
> driveway.  Once again I was unable to find the source of the smoke.
> One
> last thing to note:  at no time during any of this has the check
> engine
> light come on.
>
> This car is driving me nuts, and making me long for my '89 MTX.
> Does
> anyone have any ideas what might be causing this?
>
> Thanks in advance.
>
> J.B. Hebert
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