How to determine if a plug wire is resistor
 

1990 300e m103.
Plug wires on the car now are Autolite. Someone (PO?) transferred over the exterior metal end connectors. Is this what give the resistance, or is it internal to the plug wire?
How do I determine resistance? Specific instructions, please (put positive probe to A, put ground probe to B, etc.)
I have a multimeter and I'm not afraid to use it.:cool:

It is the wire construction itself. The metal ends have, for all practical purposes, no resistance whatsoever.

If you want to test yours, remove the wire from the car, select the ohm range on your multimeter, calibrate if necessary, then one probe on one end of the wire, the other probe on the other end. Polarity is irrelevant. Then read the resistance. Compare your reading to a metal object (a key?) to see what virtually no resistance reads. All of your wires should read similar to each other, but note that longer wires will have more resistance.

It's hard to find non-resistor wires, but it's possible, and since it sounds like those were homemade, maybe so in your case. Another easy test is radio static, since that is a principle reason they use resistor wires in passenger cars.

Hope that helps.

The leads should have copper wire cores. There should be no discernible resistance in the leads alone.
The ends which clip onto the spark plugs should be around 1000 - 1100 ohms.
Measuring end to end of any individual lead should not be more than this 1000 - 1100 ohms. (Of course this includes the metal end cap)

There is around 1000 ohms in the distributor cap per outlet and another 1000 odd ohms through the rotor button.

Here's the plug end. On this unit (Beru) there is an actual etching of the resistance.

http://farm3.static.flickr.com/2072/...902_z.jpg?zz=1

Exactly

Thanks guys. That was quick. So, basically, touch one probe to metal in one end and other probe to metal in other end and read multimeter Ohm setting?
Should be no more than 1000-1100?
Sounds easy.

The copper type leads rarely cause problems however the spark-plug connectors accumulate dust inside and become conductive .
A thorough clean-up before re-installing will help.




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Want to discount my plug wires from being an issue...
They are stamped Brem 30/06 which I assume means the are Brem made and manu date is week 30/2006...

They look fine, and have done few miles, and the resistances come in @1.1 to 1.24 K Ohms.. the 1.24 is on plug wire for #2 cylinder.

Is that good?