Spark Plug Wire Good?

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A bad spark plug wire either has a 0 reading if it's burnt through or dead. The other reading is real high, like 300 ohms or higher. Example a 2 foot wire that's ok will be around 25 to 40 ohms. If in doubt take your ohmmeter to parts store. Ask your parts guy or girl to measure a new loose wire. That way you have a reference for yours.


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A bad spark plug wire either has a 0 reading if it's burnt through or dead. The other reading is real high, like 300 ohms or higher. Example a 2 foot wire that's ok will be around 25 to 40 ohms. If in doubt take your ohmmeter to parts store. Ask your parts guy or girl to measure a new loose wire. That way you have a reference for yours.
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Your numbers are way off unless you are using metal core wires like Taylor.

Mustang5L5's number are right on track and I would use them
Ford's spec is 7K ohms per foot.

Sounds like you are below that. How does it compare to the other wires?
 
Tested a couple other wires on car and got 30 to 35 readings tested a unused 7mm wire and got zero. I am going to replace the wires but not with accels. Need 90 degree boots cause I'm putting my gt40p's on. Right now checking out why my #1 cyl reads 240 degrees at the header and the rest are at 340 to 400. Running codes and a compression test. It runs like it has a sparkplug wire plug is slack. Motor has like 30 to 40k on it but sat for awhile unused. Keep ya'll posted.
 
The 0 reading is probably because your not contacting both ends. Had the same thing happen the other day, messed around and got lead of meter to contact, reading shot up. Like mustang5L5 said your lower reading was because your setting on meter was on lower setting. Either way your wires fine that you tested. As far as lower Exaust temp on one header pipe, you could have a loss of compression/ output in that cylinder. Do a compression test, and cylinder leak down test on all 8 to see condition of engine. Also be sure theirs no blockage of Exaust or restrictions. How does car run? Loss of power? Anything out of ordinary? By the way 7.4 is 7,400 ohms! Perfectly normal.


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Runs ok does have a very slight stumble off idle when cold. I had the bucking problem with the previous motor but have resolved that by going through the check list jrichker provides on here. Ended up needed another computer. I did notice when stretch ing it out that it seens to find some power above 4k rpms kinda like when the old 4 barrel carbs kicked in if you can remember that. Other than that it's good. I need to pull codes again just to see if anything funny is goin on. I've had the rag for about 14 years and most of the problems have been self inflicted.
 
Pull codes and run the cylinder balance test portion after the last engine running codes have been flashed. To initiate the procedure, blip the throttle once the code reading is complete. The engine will idle up a tad, cut fuel to each cylinder, and see if there is a change in output to the o2 sensors. When done, a code 9 (or 9 blinks) means pass. 1-8 blinks means problem on that particular cylinder
 
You can if you want, but the switch on the clutch pedal is wired in parallel with the NGS on top of the T-5. If all of that is untouched, and this is an original 5-spd car, then either leaving the trans in neutral, or pressing the clutch in, will close the loop and prevent code 67.

If you run the codes and get code 67, press the clutch in and hold it. But then you know you have some issue with the NGS on top of the t-5
 
I'd like to hear how a low resistance wire could affect fuel to air ratio too. It's just providing an easier path for the spark to travel. Battery to coil, through module, or points if old school through wires to plugs. Ka boom!


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I'vr read over the years Rick Gorski from Firecore50 wires has done some extensive analysis on this.

http://www.yellowbullet.com/forum/showthread.php?t=321168

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