jouslee

Hey guys! Thanks for answering me question!

Now I know it sound stupid but, Do Spark Wires have continuty?
I'm asking because I tested it with my friend's multi-meter and the multi-meter declares that there is no continuity on the wires but there is resistance. And No the multi-meter is not broken.

Is that possible?

-Josh

mikaz

yes that is right. By the way resistance IS continuity.

DC350

Yeah, if they are SCREWED... or you dont know how to use your multimeter

Of course they would have continuity, you do not want resistance! Its basically just as it has been put.... Alot of resistence is ie: Bad connection, Corrosion.. too much resistance is BAD... like 0-.4 ohms but.. Ideally it would be 0 ohms resistance! but resistence is continuity


Sorry, if its a scatter brained post, had a few coronas...

DC

Sideways7

iTrader: (7)

What was the resistance? As long as it wasn't infinate, then there was continuity.

jouslee

The resistance was about 8 Ohms for the lead and 5.5-6 Ohms for the rear is that right?

mikaz

wrong, 0 ohms would probably burn out the coils. For an FC, the the plus wires should have a resistance of approx 16Kohms (16 000 ohms) per 1 meter.

Sideways7

iTrader: (7)

I don't see how that is right....

jouslee

yea that seems about what I have but why would the multimeter detect the continunity (It has an option to dected continuity, Some fancy mancy 300 dollar multi meter)

Sideways7

iTrader: (7)

but it is.... FSM says 16k. Just tested mine and its about 9k. I wonder if thats why its running so badly....
Anyway, if its measring that then it has to have continuity. Thats just how electricity works. No continuity is infinate resistance.

jouslee

that's wierd.. ok i'm gonna test the continuity on a new set of wires tommarow.
But if anyone has any more input please feel free to say something

DC350

ah, okay cool learn something new everyday!

mikaz

yupp sound right. When you first think about it, it doesnt sound right, I know. Remember we're talking about 30K volts here too. If it was just a solid length of wire, there would be so much electromagnetic and radio interference going on, none of the important electronics in the car would work right. The only application that I can think of where solid wires (~0ohms) are used are old, carburated race cars, where the interference wouldnt matter.
When you look at some other cars too, the spark plug wire layout is even important... crossing them over at certain points, not running them in parallel for any lenthths. IT can actualy induce enough voltage in the parallel wire to create an unwanted spark! Electronic stuff can be pretty crazy sometimes, interesting stuff.

mikaz

Thats what I love about this site now... time for another corona.. haha.

djturnz

I assume that your DMM has a setting that beeps when you short the leads, is that what you are using for continuity? That will only beep if the resistence is under a certain amount. The ones we use here willonly register a beep if it is under 100 ohms. Some are less.

Is the resistence of spark plug wires true resistence, or impedance?

jouslee

ahh yea thats what i figured the resistance reads something like 8.65K Ohms

turboefini88

iTrader: (1)

Spark plug wires are designed to carry a high resistance value to lessen the flow to the plugs. IE: the coil is creating 50k volts, but the plugs only need 10k to fire (just numbers dont take literally, I dont have the FSM in front of me) the resistance brings that voltage back down to the 10k the plugs need.

This is a very common practice on HEI systems. I can elaborate more later when I get home.