Spark plug wire resistance?

[AnthonyG]

Hi all, I have had a miss & found the spark plug wire I thought was the culprit. It was pretty severely corroded on the conductor termination going into the distributor cap. ( non stock Mallory crab e-distributor ). I replaced the corroded suspect termination connector for the distributor with correct tool & plugged it into the distributor with result the same a miss & no spark to that plug? I’m checking the resistance on the wire which is approx 24” & don’t know what resistance should be? Seems high @ 2000+ Ohms but really no idea what it s/b? Admitting ahead of time I’m not adept at electrical beyond checking volts and an open circuit vs a closed circuit !

Another thought, the distributor connector was so green & crusty I’m thinking it destroyed the distributor cap to which now might be the issue=Too much corrosion crud in the distributor receptor?

[Jack E/NJ]

2K seems high for metal but about right for suppression. But should see or feel spark at plug in either case. The problem seems elsewhere.

[tubman]

5000 ohms per foot on suppression wire, zero for Packard 440 and equivalent solid core wires.

[Crankster]

"Clean, bright, and shiny tight" holds true for spark plug wires too. If you have some bore bristle brushes they work pretty well for cleaning distributor cap socket receptacles. Look carefully inside the distributor cap with a strong light for evidence of cracks, carbon tracking or etching, burn marks and the like. That can cause misfire too.

[AnthonyG]

Thx all! Got a couple things to do based on your info.! Will report back.

[drolston]

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One more thing to try: After cleaning that hole on the cap, check the resistance/ohms between the connector within that receptor on the outside of the cap and the point on the inside of the cap. If the spark plug wire was not fully seated, it may jump internally, eroding the metal a causing corrosion with each firing.

[AnthonyG]

I decided the cap is so cheap @ Speedway, $18 that I just ordered it. I pulled a wire off my 40 Ford PU Truck & compared the Ohm readings with suspect wire & they were close, put suspect wire on the ‘4o & worked fine. As I know it’s the cap I’m just gonna get a new one. A set of small spiral wire brushes is the same price as the cap & as drolston indicated it could be erosion from arcing. So might as well get the new cap!
I’m sure it wil be the fix but will report back.
Thx