Q: Cylinder #2 Not Firing (1997 Ford Mustang, V6, 3.8L)

1997 Ford Mustang, V6, 3.8L - Car has lost power and engine is running rougher. - Autozone diagnosed that cylinder 2 wasn't firing. - Removed #2 spark plug wire from ignition module, held close to
module and no spark. - Swapped #2 & #6 wires and #2 wire was okay. - Cleaned and regapped #2 spark plug - didn't fix problem. - Tested #2 plug by swapping #2 & #6 wires at ignition module and saw a spark from #2 engine cylinder to #6 ignition module. - Measured primary & secondary resistance on ignition module and they were within specificaiton. - Question1: what are possible causes of no spark from ignition coil for cylinder #2 and how can I troubleshoot? Could it be a sensor or computer problem? - Question2: can I check ignition wires by measuring resistance with an ohm meter? - Comments: spark plugs need to be replaced but I don't think this is the issue.
Thanks for your help, Tony
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From your thorough diagnosis of the plug wires and the spark plugs, the next most likely part to be failing is the coil pack (ignition module) itself. It's not horribly expensive and fairly easy to replace. Probably less expensive than going to a mechanic and having the car put on their diagnostic system to confirm a bad coil pack.
You can check plug wire resistance with an ohmmeter, but you've already proven that the #2 wire is adequate because it works when connected to #6.
You should change the plugs after fixing this problem. The worn plugs aren't the source of the problem, but they do contribute to it.
Bob
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Hello Bob,
Thanks for the advice. Once concern I have about changing the coil pack is that when I measure the primary and secondary coil resistance, they were in specification. Is there anything in the coil pack other than the coil windings, like electronics?
Any thoughts on the ignition control module being the culprit? And, is this something I can troubleshoot myself?
Thanks again for your help.
Tony
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The static resistence test on a coil should be viewed this way:
If it's not within spec, the coil is bad.
If it's within spec, it does NOT prove the coil is good.
A coil can have an internal short that only appears under the application of high voltage - or heat, or vibration, etc.
Substitution with a known good part is the only sure way. If the coils are identical, swap with another cylinder and see if the problem follows the coil.
Ted
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I've seen ignition coils "ohm" good but still be faulty... They can arc internally under the higher voltages required to fire the plug. Since this cylinders running mate sounds to be working as it should and no spark is detected at the spark plug, I would consider a faulty coil pack as a very good suspect.

Hello Bob,
Thanks for the advice. Once concern I have about changing the coil pack is that when I measure the primary and secondary coil resistance, they were in specification. Is there anything in the coil pack other than the coil windings, like electronics?
Any thoughts on the ignition control module being the culprit? And, is this something I can troubleshoot myself?
Thanks again for your help.
Tony
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well first off when was the last time you changed the plugs in the car sounds like you cleaned the plugs that could be the whole problem with your car a $1.25 spark plug would cause this
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