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Discussion Starter #1 (Edited)
I'm starting to troubleshoot an ignition issue -- lately the 1300 TI has been a little hard to start, and on a recent drive, the engine cut out momentarily under acceleration, as if it had lost its spark.

So...starting with the Bosch coil, I'm getting a reading of 3.5 ohms on the primary winding, and 9.25K ohms on the secondary. My understanding is that the reading on the secondary winding is in the ballpark, but that the 3.5 ohms on the primary is high. Based on your all's collective experience, is that correct?

Oddly enough, my Brooklands shop manual says absolutely nothing about coils, ohm ranges, etc....hence reaching out to the community.

Cheers!
AA
 

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Love the title of the thread :)

The secondary resistance tells you little except perhaps to identify a coil.
Did you measure the resistance of your test leads and subtract that from the measurement of primary resistance?
If you are using points then the coil or coil + ballast resistor should be about 3 ohms.
When coils fail it is usually due to insulation breakdown and we cannot measure that without specialized test equipment. So if your motor runs well at high rpm and under full load then the coil is most likely OK.
 
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