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Discussion Starter · #1 ·
The wagon is running a little rough, I threw a timing light on it and got an erratic spark. The timing is stable, no fluctuation, but the actual strobing is erratic on all cylinders
I replaced the cap, rotor and plugs but no change, tried a different timing light to, same erratic spark. It looks just like this video (not my car)
http://youtu.be/fS2gvMwp7TM

ideas?

Thanks
 

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The wagon is running a little rough, I threw a timing light on it and got an erratic spark. The timing is stable, no fluctuation, but the actual strobing is erratic on all cylinders
I replaced the cap, rotor and plugs but no change, tried a different timing light to, same erratic spark. It looks just like this video (not my car)
http://youtu.be/fS2gvMwp7TM

ideas?

Thanks
the plug wire resistance should be checked. also condition of the wire insulation.then replace the ICM and the coil. check for corrosion on these connectors. use the white heat sink compound on the ICM heat sink..

ICM will get damaged from bad arcing wires as well as coil. then if the ICM gets too hot that also will do it.. had ICM go before in the beginning erratic spark then no spark.

that was 225K miles.
 

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You can replace the wires cheaply, and that can often be the issue. The ICM is another part that can cause the issue. I would change the wires, including the coil wire, first. Make sure they do not touch anything, or each other. The "pre cut kits" for the car that you purchase in the parts stores have one wire that is extra long and one that is too short, so take heed when installing them. If you can get a generic set, you may be able to make the wires the proper length. Check the generic set beside the "kit" set. I forget which wire is too long, but one of the shortest ones too short. You can always make a wire shorter, but you can not stretch one that is to short.

The resistance of the wires is not so much an issue as the condition of the insulation. If the wires have more than 60K on them, they are suspect.
 

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Discussion Starter · #4 ·
The wires are fairly new Mallory performance wires, I was going to replace them to but the parts store gave me the wrong wires...... They are probably OK but "Performance" parts tend to be hit or miss.... I will grab an ICM and a set of wires, they aren't that expensive.
 
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