How bad is replacing the plug wires on a 96 z26?

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GT_Indy
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Re: How bad is replacing the plug wires on a 96 z26?

Post by GT_Indy »

Rettax3 wrote:At 65k, the plugs are near or past their lifespan. At 22 years, hey, everything deteriorates with age. Corrosion can effect even the electrodes inside the engine. They are due. As for the wires, if they are original, they are as likely to come off in pieces as in one piece. They are good quality, but if you are doing one, do 'em all, it is worth a little more time.

If you do the plugs, NGKs are great, I've been using the G-Power platinums a lot lately, I used to use the V-Power nickle too. AC Delco (OE) are also a great choice. I've heard a few bad things about Bosch lately, but I still have a few engines with them and they run fine. I don't like Denso, and I don't trust Autolite anymore.

PCV valves don't actually wear out, but they only cost a few dollars, when are you going to replace them? I just do them with the plugs to be sure they are replaced before they plug-up with carbon, at least inspect it while you are under the hood, with that few miles it is likely okay.

I don't recall hearing anyone prefer to do the 3100 plugs from underneath, I'm sure a lot of people do, maybe you could let us know if it is actually easier? Ramps make short work of getting under there, for sure. My '89 GTU with the 3800 SC swap has to be done from underneath (on the rear three at least, the front bank is actually easier to access than the original 2.8 from the top), and it is a PITA to get up in there, even with the manual transmission -the autos restrict the space a lot more too.

It doesn't matter for the fuel filter if the tank is empty or not, so don't let that concern you. You only have to drop the tank to replace the pump or the strainer, the filter is outside the tank, just behind it I believe.
I think the plugs are okay as long as it ran clean and properly the whole time, I wouldn't go past 70k-75k though.
But if you don't know the history of the motor, a plug change is always a good idea.

Still a good idea to pull the plugs and check/clean them every 30k miles depending on their condition, replace early if necessary.
My engine being bought new with all new parts meant I started fresh so my plugs have no build up still, I'm a few thousand miles from my next check but I'm thinking I'll replace mine early just for my trip because I'll be loading a good 40k miles on it in the next several months with the daily driving.
Easier to fix it now at home than out in the middle of nowhere. lol :)


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Rettax3
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Re: How bad is replacing the plug wires on a 96 z26?

Post by Rettax3 »

Platinums are fine. Iridiums last longer, they don't work better. Unless you are planning on doubling your car's amazingly low mileage in the next two years (hmm, actually that wouldn't be hard, would it? :D ), the longer lasting is for mileage, NOT time -things simply degrade over time, and you don't want to leave plugs in a cylinder head (especially an aluminum one) forever. I would rarely put the extra money out for iridium -I actually put some NGK Iridium IXs in my Turbo Z-24 a few years back, but I was getting them at cost with a manufacturer's rebate on top, so they were like $2 each -hard to argue with that, and it is a high-strung high-compression turbo four-banger, so I wanted to put some tougher plugs into it just to keep things from coming apart...

Yeah, you can probably get several thousand more miles, but if you are already under the hood and popping the wires off, why bother waiting? Here is another thought - When a plug is first installed, it is gapped correctly for the so-called 'optimum' operation. From that point forward, it is eroding. The gap is slowly widening. Much less so on platinum and iridium plugs, but I've seen conventional plugs so eaten (from normal wear and age) that the gap was more than doubled -tell me this is good for the ignition system. I've seen platinum plugs wear through the platinum tip, and wow does a fine-wire plug die quickly after that happens! I've seen single-platinum plugs eat the ground electrode too -yeah the platinum went above and beyond, but there is always a limit to the design, so where is the weakest link? I've also seen the ceramic break down and generate misfires that were darn near impossible to pin down because it was intermittently shorting inside the plug, so no carbon-tracing. Final arguments for new plugs are these -if you wait a whole oil-change or even two to go back in and get these, what time of year will it be? Nice and warm out, or freeze-your-butt-to-the-ground winter time? Will you do it then, or over-run the plug's service life? Will the new wires remain 100% undamaged from an extra install and remove procedure? Will you sit there looking at the torn-out end of a was-new wire, knowing the boot and connector are still sitting behind your engine on the old #5 plug and say something that would embarrass your mother? :lol: Okay, either way, just have fun with that car, and post up some pics already! :beer:


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26
Cam2363
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Re: How bad is replacing the plug wires on a 96 z26?

Post by Cam2363 »

Rettax3 wrote:Platinums are fine. Iridiums last longer, they don't work better. Unless you are planning on doubling your car's amazingly low mileage in the next two years (hmm, actually that wouldn't be hard, would it? :D ), the longer lasting is for mileage, NOT time -things simply degrade over time, and you don't want to leave plugs in a cylinder head (especially an aluminum one) forever. I would rarely put the extra money out for iridium -I actually put some NGK Iridium IXs in my Turbo Z-24 a few years back, but I was getting them at cost with a manufacturer's rebate on top, so they were like $2 each -hard to argue with that, and it is a high-strung high-compression turbo four-banger, so I wanted to put some tougher plugs into it just to keep things from coming apart...

Yeah, you can probably get several thousand more miles, but if you are already under the hood and popping the wires off, why bother waiting? Here is another thought - When a plug is first installed, it is gapped correctly for the so-called 'optimum' operation. From that point forward, it is eroding. The gap is slowly widening. Much less so on platinum and iridium plugs, but I've seen conventional plugs so eaten (from normal wear and age) that the gap was more than doubled -tell me this is good for the ignition system. I've seen platinum plugs wear through the platinum tip, and wow does a fine-wire plug die quickly after that happens! I've seen single-platinum plugs eat the ground electrode too -yeah the platinum went above and beyond, but there is always a limit to the design, so where is the weakest link? I've also seen the ceramic break down and generate misfires that were darn near impossible to pin down because it was intermittently shorting inside the plug, so no carbon-tracing. Final arguments for new plugs are these -if you wait a whole oil-change or even two to go back in and get these, what time of year will it be? Nice and warm out, or freeze-your-butt-to-the-ground winter time? Will you do it then, or over-run the plug's service life? Will the new wires remain 100% undamaged from an extra install and remove procedure? Will you sit there looking at the torn-out end of a was-new wire, knowing the boot and connector are still sitting behind your engine on the old #5 plug and say something that would embarrass your mother? :lol: Okay, either way, just have fun with that car, and post up some pics already! :beer:
Thanks! Also should I put some antiseize on the threads if i need to replace them again?
And I've been meaning too, but I've been so busy with school and work, so I'll get around to it some day soon.

And considering I'm pretty much a new driver, I dojt think I'm going to put 65k in 2 years.

Thanks for your help! I'll keep you updated


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GT_Indy
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Re: How bad is replacing the plug wires on a 96 z26?

Post by GT_Indy »

Cam2363 wrote:
Rettax3 wrote:Platinums are fine. Iridiums last longer, they don't work better. Unless you are planning on doubling your car's amazingly low mileage in the next two years (hmm, actually that wouldn't be hard, would it? :D ), the longer lasting is for mileage, NOT time -things simply degrade over time, and you don't want to leave plugs in a cylinder head (especially an aluminum one) forever. I would rarely put the extra money out for iridium -I actually put some NGK Iridium IXs in my Turbo Z-24 a few years back, but I was getting them at cost with a manufacturer's rebate on top, so they were like $2 each -hard to argue with that, and it is a high-strung high-compression turbo four-banger, so I wanted to put some tougher plugs into it just to keep things from coming apart...

Yeah, you can probably get several thousand more miles, but if you are already under the hood and popping the wires off, why bother waiting? Here is another thought - When a plug is first installed, it is gapped correctly for the so-called 'optimum' operation. From that point forward, it is eroding. The gap is slowly widening. Much less so on platinum and iridium plugs, but I've seen conventional plugs so eaten (from normal wear and age) that the gap was more than doubled -tell me this is good for the ignition system. I've seen platinum plugs wear through the platinum tip, and wow does a fine-wire plug die quickly after that happens! I've seen single-platinum plugs eat the ground electrode too -yeah the platinum went above and beyond, but there is always a limit to the design, so where is the weakest link? I've also seen the ceramic break down and generate misfires that were darn near impossible to pin down because it was intermittently shorting inside the plug, so no carbon-tracing. Final arguments for new plugs are these -if you wait a whole oil-change or even two to go back in and get these, what time of year will it be? Nice and warm out, or freeze-your-butt-to-the-ground winter time? Will you do it then, or over-run the plug's service life? Will the new wires remain 100% undamaged from an extra install and remove procedure? Will you sit there looking at the torn-out end of a was-new wire, knowing the boot and connector are still sitting behind your engine on the old #5 plug and say something that would embarrass your mother? :lol: Okay, either way, just have fun with that car, and post up some pics already! :beer:
Thanks! Also should I put some antiseize on the threads if i need to replace them again?
And I've been meaning too, but I've been so busy with school and work, so I'll get around to it some day soon.

And considering I'm pretty much a new driver, I dojt think I'm going to put 65k in 2 years.

Thanks for your help! I'll keep you updated
If you want to use it, I wouldn't put a lot of it, antisieze can turn chalky in high heat and cause issues.
I sometimes put a tiny dot of dielectric grease on the threads before I tighten the plugs down, but it is minimal.


Cam2363
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Re: How bad is replacing the plug wires on a 96 z26?

Post by Cam2363 »

GT_Indy wrote:
Cam2363 wrote:
Rettax3 wrote:Platinums are fine. Iridiums last longer, they don't work better. Unless you are planning on doubling your car's amazingly low mileage in the next two years (hmm, actually that wouldn't be hard, would it? :D ), the longer lasting is for mileage, NOT time -things simply degrade over time, and you don't want to leave plugs in a cylinder head (especially an aluminum one) forever. I would rarely put the extra money out for iridium -I actually put some NGK Iridium IXs in my Turbo Z-24 a few years back, but I was getting them at cost with a manufacturer's rebate on top, so they were like $2 each -hard to argue with that, and it is a high-strung high-compression turbo four-banger, so I wanted to put some tougher plugs into it just to keep things from coming apart...

Yeah, you can probably get several thousand more miles, but if you are already under the hood and popping the wires off, why bother waiting? Here is another thought - When a plug is first installed, it is gapped correctly for the so-called 'optimum' operation. From that point forward, it is eroding. The gap is slowly widening. Much less so on platinum and iridium plugs, but I've seen conventional plugs so eaten (from normal wear and age) that the gap was more than doubled -tell me this is good for the ignition system. I've seen platinum plugs wear through the platinum tip, and wow does a fine-wire plug die quickly after that happens! I've seen single-platinum plugs eat the ground electrode too -yeah the platinum went above and beyond, but there is always a limit to the design, so where is the weakest link? I've also seen the ceramic break down and generate misfires that were darn near impossible to pin down because it was intermittently shorting inside the plug, so no carbon-tracing. Final arguments for new plugs are these -if you wait a whole oil-change or even two to go back in and get these, what time of year will it be? Nice and warm out, or freeze-your-butt-to-the-ground winter time? Will you do it then, or over-run the plug's service life? Will the new wires remain 100% undamaged from an extra install and remove procedure? Will you sit there looking at the torn-out end of a was-new wire, knowing the boot and connector are still sitting behind your engine on the old #5 plug and say something that would embarrass your mother? :lol: Okay, either way, just have fun with that car, and post up some pics already! :beer:
Thanks! Also should I put some antiseize on the threads if i need to replace them again?
And I've been meaning too, but I've been so busy with school and work, so I'll get around to it some day soon.

And considering I'm pretty much a new driver, I dojt think I'm going to put 65k in 2 years.

Thanks for your help! I'll keep you updated
If you want to use it, I wouldn't put a lot of it, antisieze can turn chalky in high heat and cause issues.
I sometimes put a tiny dot of dielectric grease on the threads before I tighten the plugs down, but it is minimal.
Thanks! I only ask as its something i see a lot, just put a very light coating on the threads and they come out easier.


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GT_Indy
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Re: How bad is replacing the plug wires on a 96 z26?

Post by GT_Indy »

Cam2363 wrote:
GT_Indy wrote:
Cam2363 wrote:
Rettax3 wrote:Platinums are fine. Iridiums last longer, they don't work better. Unless you are planning on doubling your car's amazingly low mileage in the next two years (hmm, actually that wouldn't be hard, would it? :D ), the longer lasting is for mileage, NOT time -things simply degrade over time, and you don't want to leave plugs in a cylinder head (especially an aluminum one) forever. I would rarely put the extra money out for iridium -I actually put some NGK Iridium IXs in my Turbo Z-24 a few years back, but I was getting them at cost with a manufacturer's rebate on top, so they were like $2 each -hard to argue with that, and it is a high-strung high-compression turbo four-banger, so I wanted to put some tougher plugs into it just to keep things from coming apart...

Yeah, you can probably get several thousand more miles, but if you are already under the hood and popping the wires off, why bother waiting? Here is another thought - When a plug is first installed, it is gapped correctly for the so-called 'optimum' operation. From that point forward, it is eroding. The gap is slowly widening. Much less so on platinum and iridium plugs, but I've seen conventional plugs so eaten (from normal wear and age) that the gap was more than doubled -tell me this is good for the ignition system. I've seen platinum plugs wear through the platinum tip, and wow does a fine-wire plug die quickly after that happens! I've seen single-platinum plugs eat the ground electrode too -yeah the platinum went above and beyond, but there is always a limit to the design, so where is the weakest link? I've also seen the ceramic break down and generate misfires that were darn near impossible to pin down because it was intermittently shorting inside the plug, so no carbon-tracing. Final arguments for new plugs are these -if you wait a whole oil-change or even two to go back in and get these, what time of year will it be? Nice and warm out, or freeze-your-butt-to-the-ground winter time? Will you do it then, or over-run the plug's service life? Will the new wires remain 100% undamaged from an extra install and remove procedure? Will you sit there looking at the torn-out end of a was-new wire, knowing the boot and connector are still sitting behind your engine on the old #5 plug and say something that would embarrass your mother? :lol: Okay, either way, just have fun with that car, and post up some pics already! :beer:
Thanks! Also should I put some antiseize on the threads if i need to replace them again?
And I've been meaning too, but I've been so busy with school and work, so I'll get around to it some day soon.

And considering I'm pretty much a new driver, I dojt think I'm going to put 65k in 2 years.

Thanks for your help! I'll keep you updated
If you want to use it, I wouldn't put a lot of it, antisieze can turn chalky in high heat and cause issues.
I sometimes put a tiny dot of dielectric grease on the threads before I tighten the plugs down, but it is minimal.
Thanks! I only ask as its something i see a lot, just put a very light coating on the threads and they come out easier.
Yah it does help, some used cars I've had I remember the plugs and O2 sensor being so tight I had to use a breaker bar and I was concerned for the heads/pipe, etc.
There is an antisieze grease made for spark plugs that can handle the heat and still let it conduct the ground.

On my O2 sensors I use regular antisieze because its just an exhaust pipe, worst case I cut and replace, but antiziese always made it come out easy.

I have used antiziese on spark plugs in the past, it can be used, but it will turn chalky from the heat, still better than nothing as it still seems to be helpful.


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Rettax3
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Re: How bad is replacing the plug wires on a 96 z26?

Post by Rettax3 »

Cam2363 wrote:Thanks! Also should I put some antiseize on the threads if i need to replace them again?
And I've been meaning too, but I've been so busy with school and work, so I'll get around to it some day soon.

And considering I'm pretty much a new driver, I dojt think I'm going to put 65k in 2 years.

Thanks for your help! I'll keep you updated
I use a light coating of anti-seize unless I am just being lazy -on aluminum heads it is a good idea, GM actually applied it on some of them from the factory. It doesn't matter which type you use -C5-A, standard copper, aluminum-based, or high-heat aluminum, they are all rated for well over CHT (Cylinder Head Temp). Copper is rated for higher temps generally, but Napa offered a Permatex high-heat aluminum-based with a higher rating than standard copperAll of them conduct ignition voltage just fine too. I tend to use aluminum on aluminum heads and copper-based on iron heads, but that is just me. I also use copper-based on exhaust hardware, but prefer aluminum-based on wheel lug-studs -that is just preference though. GT_Indy is correct -it will get chalky under heat if you use too much, but I have NEVER heard of anyone using dielectric grease on plug threads, I don't know that it would do any harm, but I would not recommend that. :unknown:


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26
Cam2363
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Posts: 333
Joined: Sun May 20, 2018 5:35 pm

Re: How bad is replacing the plug wires on a 96 z26?

Post by Cam2363 »

Rettax3 wrote:
Cam2363 wrote:Thanks! Also should I put some antiseize on the threads if i need to replace them again?
And I've been meaning too, but I've been so busy with school and work, so I'll get around to it some day soon.

And considering I'm pretty much a new driver, I dojt think I'm going to put 65k in 2 years.

Thanks for your help! I'll keep you updated
I use a light coating of anti-seize unless I am just being lazy -on aluminum heads it is a good idea, GM actually applied it on some of them from the factory. It doesn't matter which type you use -C5-A, standard copper, aluminum-based, or high-heat aluminum, they are all rated for well over CHT (Cylinder Head Temp). Copper is rated for higher temps generally, but Napa offered a Permatex high-heat aluminum-based with a higher rating than standard copperAll of them conduct ignition voltage just fine too. I tend to use aluminum on aluminum heads and copper-based on iron heads, but that is just me. I also use copper-based on exhaust hardware, but prefer aluminum-based on wheel lug-studs -that is just preference though. GT_Indy is correct -it will get chalky under heat if you use too much, but I have NEVER heard of anyone using dielectric grease on plug threads, I don't know that it would do any harm, but I would not recommend that. :unknown:
Thanks! Ill definitely make sure I use it, along with the dielectric grease on the wires only


Cam2363
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Posts: 333
Joined: Sun May 20, 2018 5:35 pm

Re: How bad is replacing the plug wires on a 96 z26?

Post by Cam2363 »

GT_Indy wrote:
Cam2363 wrote:
GT_Indy wrote:
Cam2363 wrote:
Rettax3 wrote:Platinums are fine. Iridiums last longer, they don't work better. Unless you are planning on doubling your car's amazingly low mileage in the next two years (hmm, actually that wouldn't be hard, would it? :D ), the longer lasting is for mileage, NOT time -things simply degrade over time, and you don't want to leave plugs in a cylinder head (especially an aluminum one) forever. I would rarely put the extra money out for iridium -I actually put some NGK Iridium IXs in my Turbo Z-24 a few years back, but I was getting them at cost with a manufacturer's rebate on top, so they were like $2 each -hard to argue with that, and it is a high-strung high-compression turbo four-banger, so I wanted to put some tougher plugs into it just to keep things from coming apart...

Yeah, you can probably get several thousand more miles, but if you are already under the hood and popping the wires off, why bother waiting? Here is another thought - When a plug is first installed, it is gapped correctly for the so-called 'optimum' operation. From that point forward, it is eroding. The gap is slowly widening. Much less so on platinum and iridium plugs, but I've seen conventional plugs so eaten (from normal wear and age) that the gap was more than doubled -tell me this is good for the ignition system. I've seen platinum plugs wear through the platinum tip, and wow does a fine-wire plug die quickly after that happens! I've seen single-platinum plugs eat the ground electrode too -yeah the platinum went above and beyond, but there is always a limit to the design, so where is the weakest link? I've also seen the ceramic break down and generate misfires that were darn near impossible to pin down because it was intermittently shorting inside the plug, so no carbon-tracing. Final arguments for new plugs are these -if you wait a whole oil-change or even two to go back in and get these, what time of year will it be? Nice and warm out, or freeze-your-butt-to-the-ground winter time? Will you do it then, or over-run the plug's service life? Will the new wires remain 100% undamaged from an extra install and remove procedure? Will you sit there looking at the torn-out end of a was-new wire, knowing the boot and connector are still sitting behind your engine on the old #5 plug and say something that would embarrass your mother? :lol: Okay, either way, just have fun with that car, and post up some pics already! :beer:
Thanks! Also should I put some antiseize on the threads if i need to replace them again?
And I've been meaning too, but I've been so busy with school and work, so I'll get around to it some day soon.

And considering I'm pretty much a new driver, I dojt think I'm going to put 65k in 2 years.

Thanks for your help! I'll keep you updated
If you want to use it, I wouldn't put a lot of it, antisieze can turn chalky in high heat and cause issues.
I sometimes put a tiny dot of dielectric grease on the threads before I tighten the plugs down, but it is minimal.
Thanks! I only ask as its something i see a lot, just put a very light coating on the threads and they come out easier.
Yah it does help, some used cars I've had I remember the plugs and O2 sensor being so tight I had to use a breaker bar and I was concerned for the heads/pipe, etc.
There is an antisieze grease made for spark plugs that can handle the heat and still let it conduct the ground.

On my O2 sensors I use regular antisieze because its just an exhaust pipe, worst case I cut and replace, but antiziese always made it come out easy.

I have used antiziese on spark plugs in the past, it can be used, but it will turn chalky from the heat, still better than nothing as it still seems to be helpful.
Thanks! Ill have to check if there is a sparkpug specific grease, but it probably is just normal grease that the price was raised on lol. But Ill definetly look


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