Measuring resistance in a spark plug wire

[jremington59]

I have a skip in my 97 4.0 exp. I misted the wires with water and had an arc on one wire. I pulled the wire and checked the ohms and got a reading of 14.34K on my meter which registers from 0 to 20,000,000 ohms. The wire is a little over 2 foot.

I'm not real experienced with meters, but wouldn't that mean 14,340 ohms of resistance? Also, shouldn't a good wire be less than 4.0k ohms resistance per foot?

 

[2000StreetRod]

Resistance per foot

According to the article at the following link, MSD ignition helically wound wire has a resistance of 40 to 50 ohms per foot. I don't know if that is typical. I just measured one of my wires (about 14 inches long) and the resistance was 6.3Kohms. Your 14.3Kohms for 2 feet seems comparable.

MSD 8.5mm Super Conductor Spark Plug Wires 32559

 

[Runnin'OnEmpty]

Yep, normal resistance for stock wires is about 5-8K ohms per foot
of wire. I suspect the arcing was from a loose or broken terminal end.

A sparkplug will also have an internal resistance of about the same,
normally 5-6K ohms.

 

[bluestream1]

http://www.ehow.com/how_2296047_test-spark-plug-wire-car.html

 

[firepop5]

Are the wires original? Even if they aren't, if you have arcing, they should be replaced regardless of resistance.

 

[budwich]

You have 5 others to compare your readings with... but I suspect that its correct. Anyways, arching is an insulation problem not usual a conduction / resistance problem.

 

[jremington59]

Thx everyone. I found the problem. A plug was cracked.

It's nice to know how to check the wires now though. When you take a reading, what does the k stand for in 14k ohms?

 

[budwich]

just like in other things (kilometer - km), its "short" for 1000.... and in your case 14 000 ohms.