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How much resistance is present in OEM spark plug wires?
#1
MBWorld Fanatic!
Thread Starter
How much resistance is present in OEM spark plug wires?
The reason i ask is im looking at plugs and wires here shortly so out of curiosity I pulled some spark plug wires, and was surprised to see over 1K ohms resistance. Is this right or are my wires ancient and no longer providing an easy path for electricity?
#2
MBWorld Fanatic!
I think it is stamped on the metal portion of the plug wire? (if my memory is working correctly)
For some reason 2k Ohm rings a bell-- maybe thats older cars tho.
For some reason 2k Ohm rings a bell-- maybe thats older cars tho.
#4
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Thread Starter
Yea some were right around 2Kohms, others less, other way more (4-5Kohms...???) seems the highest resistance is coming from the wires closest to the driver.
#5
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2003 E55 AMG
The resistance of a spark plug wire or any wire for that matter, is dependant on 3 variables. One is the resistivity of the wire (different metals will have different resistances depending on their electron configuration in their outer shell), one is the length of the wire being measured, and one is the cross section or area of the wire.
Resistance = Resistivity of wire material x(Length/cross sectional area).
Given the higher resistance from the drivers side wires, I would conclude they are simply longer than the oassenger side wires.
Edit* forgot to mention that the temperature of the wire will also affect the resistance. Typically with certain exceptions, as a metal becomes hotter, the resistance will increase. This can be somewhat misleading though as far as measuring goes, since the metal will also expand at higher temps, increasing the area of the wire and counteracting the effects of the heat.
Resistance = Resistivity of wire material x(Length/cross sectional area).
Given the higher resistance from the drivers side wires, I would conclude they are simply longer than the oassenger side wires.
Edit* forgot to mention that the temperature of the wire will also affect the resistance. Typically with certain exceptions, as a metal becomes hotter, the resistance will increase. This can be somewhat misleading though as far as measuring goes, since the metal will also expand at higher temps, increasing the area of the wire and counteracting the effects of the heat.
Last edited by BenJ; 06-08-2012 at 03:29 AM.
#6
MBWorld Fanatic!
The resistance of a spark plug wire or any wire for that matter, is dependant on 3 variables. One is the resistivity of the wire (different metals will have different resistances depending on their electron configuration in their outer shell), one is the length of the wire being measured, and one is the cross section or area of the wire.
Resistance = Resistivity of wire material x(Length/cross sectional area).
Given the higher resistance from the drivers side wires, I would conclude they are simply longer than the oassenger side wires.
Edit* forgot to mention that the temperature of the wire will also affect the resistance. Typically with certain exceptions, as a metal becomes hotter, the resistance will increase. This can be somewhat misleading though as far as measuring goes, since the metal will also expand at higher temps, increasing the area of the wire and counteracting the effects of the heat.
Resistance = Resistivity of wire material x(Length/cross sectional area).
Given the higher resistance from the drivers side wires, I would conclude they are simply longer than the oassenger side wires.
Edit* forgot to mention that the temperature of the wire will also affect the resistance. Typically with certain exceptions, as a metal becomes hotter, the resistance will increase. This can be somewhat misleading though as far as measuring goes, since the metal will also expand at higher temps, increasing the area of the wire and counteracting the effects of the heat.