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Discussion Starter #1
I bench tested the leads with a multimeter and they passed. When I Bench test with a trouble light they fail the test. Why? Because of too much resistance in the connector that fits the plug?
 

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Never thought about it, but I guess so....they are designed to let tens of thousands of volts pass, not 12V

what multimeter test did you do?
The Ohms resistance will vary according to length of lead, but what do you compare it to apart from an identical set of brand new leads. (Rule of thumb is about 5-8 k.Ohms / foot length for normal leads)

The better test is to securely clamp the DVM with crocodile clips (set to say 20 k.ohms) firmly to each end of the Plug lead then wiggle and bend it about....each lead should read rock steady. If it fluctuates it is breaking down inside.
 

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Discussion Starter #3
The multimeter test was in the ballpark Ohms wise.
 

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I don't think continuity or resistance is as much a factor as poor connections . There is lots on the net. If you suspect your car isn't responding to a tune-up, it's probably because bad leads are the cause.
 

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Discussion Starter #5
i Installed new wires with older connectors. I just wanted to be sure they were good because when I get my Spider back together (I’m doing a major engine bay restoration) and I have electrical issues I will know at least my leads are good.
 

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The multimeter test was in the ballpark Ohms wise.
What is the size of your ballpark, maximum and minimum?

Different types of wire have different resistances. If you know the ohms/foot of your cables and you calculate the expected resistance and they are within 10% then they might be OK. But HT wires also fail by insulation breakdown and you cannot measure that with a multimeter. If you can touch the wires with the engine running and not spill your beer then the insulation is OK.
 

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And if the insulation is leaking you can use the old trick of using your wife's hairspray to seal them up.
 

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Plug wire Insulation breakdown is not a surface condition and will not be fixed by a thin coat of anything.
 

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Very true. Leads breakdown internally...the best test you can do on leads is replace them with new if you do not know their age. It is one of the best and easiest tune ups anyone can do
 

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Plug wire Insulation breakdown is not a surface condition and will not be fixed by a thin coat of anything.
Of course you are right Ed. This is a temp fix at best. Replacement is by far the only real solution. I posted this mostly as a joke. My sense of humor gets me in trouble regularly, just ask my wife!
 

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Discussion Starter #12
Thanks everyone. I think I will install all new stuff.
 
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