Short spark plug wires - worth changing?

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SE British Columbia, Canada
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Has anyone seen a definitive improvement in idle from changing those 9 inch spark plug wires that run from each coil on top the valve cover to the spark plug? With such a short distance, I'm wondering if degradation really happens. This is on a GM LS V-8. With long wires, cooking between engine and firewall on a transverse V-6, I would think degradation would be more prevalent. My wires are 12 years old and have 205,000 miles on them. The idle is not quite as smooth as when the truck is new. The spark plugs are only a year old. Thanks.
 
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Tn.
When to change spark plug wires — Ricks Free Auto Repair ... https://ricksfreeautorepairadvice.com/when-to-change-spark-plug-wires Jun 23, 2012 · So it makes no sense to try to squeeze more life out of old spark plug wires. And, since most later model car engines run almost 100,000 miles on a set of spark plug, it's best to change the spark plug wires when you change the plugs. What's the difference between a good set of spark plug wires and an economy set. It's all in the insulation. PS--- every 100,000 miles sounds goood to me
 
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14,539
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Santa Barbara, CA
I did them with my truck, but I kinda had to since the old ones came off in pieces. I wanted to use something cool like the Accel ones that have the ceramic boots but this was an emergency situation so I got ACDelco.
 
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The Northeast
Makes sense for the wires near certain areas, like the hot exhaust manifold, to take more of a beating. Regardless, if they come as a full set might as well replace them all. They're probably tired @205k anyway.
 
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Texas
If you think plug wires may be going bad , raise the hood at night , with the engine running . Listen and watch for spark jumping , in the dark . God bless Wyr
 
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Fort Worth, Texas
if it still pulls strong under heavy load tip-in situations.....The plug wires are fine! The KV spike in this transition is pretty phenomenal & the spark will find a easier path to ground if it possibly can! I would have recommended replacement because it would suck to be out somewhere towing & have one break down on you.
 
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