Ignition Wires

RAK

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Are the spark plug wires supposed to be changed when replacing the old spark plugs? The owner's guide indicates the mileage as to when to install new plugs, but there is no mention of the ignition wires. Any input would be helpful---thanks in advance!
 
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Only if there's a problem. Conventional high-voltage cables (if that's what you have) are simple to check with an ohmmeter.
 
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My interesting observation with my Nissan Sentra... 1995... Car started running not so good.. . So I changed rotor, distributor cap, plugs... Car ran better but still had a noticeable miss at times... went back to AAP... Got spark plug wires... Last thing I could think of to do and then it was on to the fuel system... Sure enough started the car up and it ran perfect... Two years later car started missing a bit again... I just changed the wires and it got the car running right again. . On a old school type set up with rotor, distributor cap... The wires should be changed... New setup like my 08 Nissan Altima 3.5 I have had the plugs only changed two times... No wires needed changing.
 
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you can check ohms and also run the car in total darkness and look for very faint/dim arcing like static electricity appearance. new cars with COP's won't need anything except a coil and recommend to do all at the same time
 
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I think you are right ^^^^^^^^↑ Change all coils at the same time... My cars coils are like 95 bucks per coil... Near $600 for all six.... Makes plugs look cheap by comparison LOL At 7.99 a plug Denso iridium TT plugs... And changing plugs help keep coils from going into failure mode...
 
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Originally Posted by bbhero
I think you are right ^^^^^^^^↑ Change all coils at the same time... My cars coils are like 95 bucks per coil... Near $600 for all six.... Makes plugs look cheap by comparison LOL At 7.99 a plug Denso iridium TT plugs... And changing plugs help keep coils from going into failure mode...
Others will disagree, but when coils get close to 200K miles, I like to change them. I use Denso, as they are OEM to many supplies. As you know, factory coils are pretty dang pricey.
 
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I have a vehicle (Ford 4.0L OHV Cologne) that still uses wires. The AutoZone Duragold last about 50-60k miles. I change the spark plugs about half that interval. Had a VR6 12V that also used wires. Had it until 140k miles on the original wires.
 
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Originally Posted by JeffKeryk
Originally Posted by bbhero
I think you are right ^^^^^^^^↑ Change all coils at the same time... My cars coils are like 95 bucks per coil... Near $600 for all six.... Makes plugs look cheap by comparison LOL At 7.99 a plug Denso iridium TT plugs... And changing plugs help keep coils from going into failure mode...
Others will disagree, but when coils get close to 200K miles, I like to change them. I use Denso, as they are OEM to many supplies. As you know, factory coils are pretty dang pricey.
Yeah I have 305k miles on my original coils. . Still runs very well... Not too shabby.
 
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Vehicles like a GM 3800 series motor require new spark plugs every 100k miles. In this engine you nearly destroy the OE wires coaxing them out particularly the back 3 on the first plug swap and you'll need new wires. If we're talking about the car in your sig and they're original wires, do it.
 
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I do plug wires at every spark plug change. They are not that expensive and they usually get damaged on removal anyhow. The heat of the engine bay and ozone all take a toll on the wires as well.
 
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Spark plug wires last a long time. If you have any suspicions, spray them lightly with water at night. If you do not have a light show and resistance doesn't exceed 5k ohms per foot, they are still good.
 
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Back in the days of secondary wires, only PACKARD knew the secret to make good performing and reliable ignition wire. Even Nippon Denso would import bulk wire to Japan to build wire sets. You will see this on the older Subaru. There was something special in the latex insulation under the Hypalon jacket that seemed to make it more resistant to arcing or jumping. Remember the internal resistance "wire" is just graphite on fiberglass then wrapped with tape. You cant run copper or steel wire unless its tight "spring wound" to suppress radio noise ( EMI/ RFI). These system are designed to work with a synergy, you cant just willy-nilly "change the circuit" by changing R/L/C values by going to MAG wire. Old timer trick; Tune a Am pocket radio to either end of the band (1610 khz) turn it on, and move it around the wires. You will hear "snapping "through the speaker if there is a leaky wire. If you suspect a bad wire, you can move the wires a bit where they bend or touch the rocker cover(s) or the block or exhaust heat shielding.. Also look for "spark shows" at night. HEI used to develop a corona over the ceramic plug insulators in humid weather. This is why keeping the plug insulators pristine is so important in a tune up. It's a "white glove" kind of job. Treat them like Quartz Iodine bulbs. -Ken
 
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I decided to change my wires around 190k just for the heck of it. Car ran the exact same before & after. Read later that Honda wires at least tend to last forever.
 
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Originally Posted by mclasser
I decided to change my wires around 190k just for the heck of it. Car ran the exact same before & after. Read later that Honda wires at least tend to last forever.
The #1 and #4 plug wires on my Mazda lasted the whole 606k miles and 34 years the car was around. The other two failed repeatedly, I assume because the boots on the plugs were subjected to higher temperature in the middle positions. The distributor-to-coil wire failed at the coil end at around 550k. The resulting arcing took out the original coil because I didn't notice the cable failure promptly.
 
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Modern plugs can go 100,000 miles or more before replacement, so it kinda depends on your usage. If you don't drive a lot (or got a used car that sat around) and your wires are 15 years old or more, I would change them when changing plugs. But if you drive a lot (or got a high mileage used car) and need new plugs but the wires are less than 10 years old, I would leave them if it's running OK. Last year I changed the plugs and wires in the Corvette even though it's only got 75,000 miles, because I'm pretty sure everything is original and 25 years old. Stuff that old is more likely to fail (wires) or seize (plugs).
 
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If you are worried, change them. Cheap insurance. You can test them like others have said, be sure to move the wire around as you check to ensure the wires are good. Also look for any obvious physical indications they may be bad. Just use a quality set of wires to replace them with, I am also a fan of NGK or the factory set.
 
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Originally Posted by ARCOgraphite
Back in the days of secondary wires, only PACKARD knew the secret to make good performing and reliable ignition wire. Even Nippon Denso would import bulk wire to Japan to build wire sets. You will see this on the older Subaru. There was something special in the latex insulation under the Hypalon jacket that seemed to make it more resistant to arcing or jumping.
Yep....Packard made the best plug wires in the world for a few decades, I still run across a old 3.8L with original Packard wires on it every once in a awhile!
 
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Brings back some old memory's Remember seeing these Packard Wires on my fathers old Buick's.
 
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