Plug wire test?
#1
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Hey guys. I was wondering if there is any way to test the plug wires on my 81'. Can I use a digital vom to check the resistance of the wires? What should they ohm out to? Are there any other tests that can be performed? My car is running fine now,and I am just doing this as preventative maitnence. I don't want to put out the bucks for a new set if I am not positive they need replacement. <img border="0" alt="[cheers]" title="" src="graemlins/beerchug.gif" />
#2
928 Engine Re-Re-Rebuild Specialist
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There's always the "firefly" test.
Park your car in a completely dark place with the engine running and look under the hood. Small sparks (i.e. "fireflies") signal that your wires need to be replaced.
Park your car in a completely dark place with the engine running and look under the hood. Small sparks (i.e. "fireflies") signal that your wires need to be replaced.
#4
Nordschleife Master
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It is possible that your wire will not produce the "fireflys" under low humidity, but will do so under weter conditions.
To test, get a mist bottle, and mist the wires while preforming the "firefly" test. Do not soake the engine compartment down. Just mist 'em. Like a used pump hair spray bottle works fine.
To test, get a mist bottle, and mist the wires while preforming the "firefly" test. Do not soake the engine compartment down. Just mist 'em. Like a used pump hair spray bottle works fine.
#5
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Since the resistance in the secondary system is a separate 3 kOhm resistor on each plug wire, and the wires have close to no resistance, each wire should measure essentially the same 3 kOhm resistance.