Update: 1991 Accord - No Start - No Spark

I posted a question regarding no-spark on a '91 Accord last week. Problem solved: It was the coil. That is so strange considering the car ran when parked. I figured a bad coil would cause a breakdown, not
a no-start.
Diagnosis went like this (steps 1-5 done before the last post):
1. Key on causes fuel pump to cycle. Thus, ECM probably okay.
2. Checked spark at a cylinder - nothing.
3. Verified cam was turning through oil filler cap: Cam turns, timing belt must be okay.
4. Removed cap, checked spark from coil high tension post: Nothing.
5. Checked coil resistance - .7 ohms low side, 12k ohms high side (disregard last post on this - I measured the high side incorrectly). Note: These readings are in-spec!
6. Removed ignitor from distributor and performed bench test procedure from tegger.com - Passed!
7. Bench tested the coil: No spark from high side to ground - BUT, just enough to cause a mild shock from high side to _positive_ terminal of low side. Looks like a bad coil.
8. Connected small light bulb in place of the coil and cranked the engine: Light flashes.
Number 8 was what finally convinced me to replace the coil. Installed a new one and the engine fired right up. I went ahead and replaced the cap, rotor, plugs, and wires because their condition undoubtedly caused the problem to begin with.
Thanks Elle, Jim Yanik, Thom, motsco, and Tegger!
-rev
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If the internal coil insulation breaks down at HV,you could get a good resistance reading at the low volts any meter uses for measuring ohms,(IIRC,~2volts)but when the coil pulses,the HV breaks down the insulation and effectively shorts itself out,thus not enough voltage to make a spark.
Good to hear your problem is solved!
--
Jim Yanik
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