While reading Rob's story about his car not firing, it reminds me of a
problem I had.
After being out of commission a long time (I don't recall what repair was
stopped half way through the process) I put the car back together and went
to crank her up.
The sucker wouldn't fire. Not even a cough. Or a sputter.
I could tell I was getting fuel . . . Cranked the engine with the spark
plugs out and could smell it jetting out the plug holes.
I had also resorted to starting fluid at one point. So fuel wasn't the
problem.
I had checked and double checked the timing and to the best of my knowledge,
it was correct.
I hooked up my inductive timing light and it was flashing regularly on all
cylinders.
What the hell was wrong?
I eventually found out. It was my spark plugs.
I guess when I took them out there were particularly sooty or oily or
something, and I can only guess that I cleaned them off with something like
a tiny dremmel wire wheel.
Apparently I didn't really clean them . . . instead I smeared an electrical
path of less resistance all over the insulator and between conducting
surfaces.
So what I was getting was pulses of electricity to the plugs, but no
"spark."
The electricity just dispersed across the aforementioned "smear."
That's my theory anyway .. Dave or Randall can tell me if it sounds
plausible.
Whatever the cause .. . I spent a LONG time scratching my head trying to
figure out what was wrong, when all it took was a new set of spark plugs.
(or a clean set anyway)
So there's my lesson for you . .. the inductive timing light is only sensing
CURRENT flowing through the wires.
It isn't sensing that there is an actual spark that will ignite a fuel air
mixture.
In my case .. new plugs .. and it fired right up and drove BEAUTIFULLY.
To think of all that time I wasted. . . That car probably sat for months
cause I couldn't figure out why it wouldn't start.
Scott Tilton
Program Engineer / Rapid Prototyping
Prototype Productions, Inc.
21641 Beaumeade Circle
Suite 311
Ashburn, VA 20147
http://www.protoprod.com/ <http://www.protoprod.com/>
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