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Subject:Re: What did I destroy now? (Ignition fail)
From:David Beierl
Date:Thu, 11 Feb 2010 15:24:36 -0500

At 01:57 PM 2/11/2010, Robert Fisher wrote:
>I know I need to go through the procedures in the book and test all kinds of
>crap but right now I'm more of a mind to set the damn thing on fire so I
>thought I'd see if y'all had some pointers before I go back out there.
>In the meantime I'm topping off the battery and I'm going to hang out inside
>and cool down.

Dear Robert,

I'd start by holding the coil wire a quarter-inch or so from ground
while someone cranks.  If you get a nice fat spark then try the same
with one of the plug wires, and if there's the same good spark there,
try it using the spark plug as well.  If these are all good, seems
more than likely that ignition is not your problem.

If you get no spark from the coil wire, check for +12 at the coil
positive, then hook a neon-light circuit tester between the coil
negative and ground (without removing any wires).  Or if you're
feeling adventurous, you could use your finger while holding on to
ground with the same hand.  Probably no need to lick your fingers,
since that terminal should pulse to 120 volts or so on each firing
impulse.  Using the same hand should keep any current out of your
heart, but if you suddenly wake up dead you're responsible entirely
(Lawyer: "Doctor Expert, isn't it true that if you die while asleep
you won't know it until you wake up in the morning?"  Doctor on
stand: "Counsellor, did you graduate from eighth grade?").  If no
activity there, check the Hall Sender wires while cranking -- one
should be ground, one five volts, and the third one should pulse
between zero and five volts.   If your voltmeter won't show pulsing,
try an LED with a thousand ohms in series, or if you have access use
the correct tool, which is a logic probe (~$20 I think) or oscilloscope.

If you have pulsing on the Hall Sender line and not at the coil
negative, then it's either a bad connection between distributor -->
ECU --> coil or else a bad ECU.

Yours,
David