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Discussion Starter · #1 ·
It's my understanding that the 99-04 stock plugs are platinum. I've heard that they have a life span of about 100,000 miles but iridium lasts 200,000 miles. I was wondering if it's worth replacing the platinum with iridium? I'm not sure if I'll still have my 02 that long. It's been a long time since I changed a spark plug and I've heard that it's a bit different now.
 

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Iridium- longer life weaker spark.
Copper- “strongest” spark shorter life, best priced.
Platinum- Somewhere in between.
But really though, a spark is a spark as long as it’s lighting things off.
These fit yours and provide the “best” spark. They’ll last a good while. We’re not talking about changing them every oil change or anything like that. But if you don’t need new plugs now it’s not worth wrestling with them.
 

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Iridium- longer life weaker spark.
Copper- “strongest” spark shorter life, best priced.
Platinum- Somewhere in between.
Exactly what I started to say, but didn’t what to deal with a “prove it” post.
 
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Iridium has a weaker spark than platinum? I thought I read the opposite a long time ago. I know copper is definitely superior for conducting electricity but they wear pretty fast comparatively speaking.
 

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Well, it seems to depend on who does the comparison, and what “BEST” means to you. I’ve read each is superior to the other with the reviewer’s listed reasons and vise-versa. Hence the reason I said stick with what you know works for the car.

Copper produces a fatter, cooler spark and is cheaper to produce. It is often recommended for high-compression & turbo charged engines, but doesn’t last as long.

Platinum maintains a sharper firing edge and lasts longer than copper because it’s a harder martial. It’s a thinner spark than copper, and runs hotter.

Iridium uses a fine wire center, and produces the most narrow spark. Being harder than Platinum or copper, it lasts longer, but costs substantially more.

You can find all sorts of reasons to pick one over the other depending on who writes the articles. I really don’t KNOW factually which is best for a particular engine, so I stick with what has been working well.

Brisk Spark Plugs also offer differing information, and according to some write-ups, they are superior to all other plugs regardless of type. Other write-ups indicate that if your goal is to destroy your engine, Brisk is your brand. For me, it’s just less dramatic and less worry to replace with what you already know works well.

Just my 2¢ - Nothing authoritative
 

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Discussion Starter · #7 ·
One article I read stated that platinum is being used because of the difficulty of getting to the spark plugs in a lot of cars. And because of the location of the plugs, iridium is preferred. The idea is that the most trouble free plugs should be used where it's very difficult to get to the plugs. Hopefully, I won't have to mess with the plugs like I did 30 years ago. So far my Mustang plugs have been reliable over the past 19 years (68,000 miles). Overall, the Mustang has been reliable. But it would have been nice if there had been a tow ring on it to get me out of mud........
 

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It's my understanding that the 99-04 stock plugs are platinum. I've heard that they have a life span of about 100,000 miles but iridium lasts 200,000 miles. I was wondering if it's worth replacing the platinum with iridium? I'm not sure if I'll still have my 02 that long. It's been a long time since I changed a spark plug and I've heard that it's a bit different now.
IMHO, you can run a plug 100K miles but that doesn't mean you should! I change mine out about every 35K miles.....
 
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The platinum plugs are good for 100k easy with no noticeable loss of performance. Changing anything that much sooner will usually ensure that you have a reliable part in your car but imo it's a waste of hard earned $ given their life expectancy. Platinum is hella durable compared to copper.
 

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I have a Denso Iridium IK20 Simcasts spark plug. No problem here... As far as I know about spark plugs, the differences are not big, use the ones you used.
 

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Discussion Starter · #11 ·
IMHO, you can run a plug 100K miles but that doesn't mean you should! I change mine out about every 35K miles.....
I have just under 70,000 on my 02. Maybe this would be a good time to change them out. But, I don't think I'm going to go for the iridium ones. It'll be interesting to see how these plugs come out since it's my understanding that it isn't as simple as taking off the spark plug wire to remove them like in the old days. Thank goodness for youtube.

I have a Denso Iridium IK20 Simcasts spark plug. No problem here... As far as I know about spark plugs, the differences are not big, use the ones you used.
I think the OEM plugs are platinum so I'll stick with that.
 

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Discussion Starter · #14 ·
Do you have to replace the coils also? I've been watching some youtube videos and it isn't clear how to remove the spark plugs.

Hmm, I need to buy more tools. Like a torque wrench.
 

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Do you have to replace the coils also? I've been watching some youtube videos and it isn't clear how to remove the spark plugs.

Hmm, I need to buy more tools. Like a torque wrench.
Things you’ll need for removal: Ratchet, extension, and spark plug socket. It’s a socket with a rubber in it.
How to remove: Unscrew the screw that is holding the coil down. Pull up and remove the coil. Then, stick the extension and socket that are connected to the ratchet into the hole to seat the socket around the spark plug. Once the socket is aligned properly and seated, turn the ratchet to the left. Go slow at first. If they haven’t been changed in awhile spray some penetrating oil in the holes first and let it sit awhile before you try to remove them. When you tighten them down get them tight, but don’t be the Incredible Hulk. Once they stop getting tighter stop.
 

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I was looking at NGK spark plugs and the specs says they're nickel?
I think the core is copper.
This is true. They are nickel plated copper.
Copper plugs are usually plated with nickel because of copper's relatively low melting point. Right out of the box they aren't conducting from raw copper until they wear but by then they're giving less performance because the sharp edges of the copper conductor don't last for long in the high cylinder temps which leads to less efficiency. Also, the gap increases as they continue to dull and degrade. Platinum and especially now iridium have cured these issues and that's why they last for so very long. Other than forced induction applications I really don't see much need for copper plugs in a modern engine.
I put iridiums in my 1991 GT and it seemed to like those plugs. They seemed to give me a very tiny bump in MPG though that might have just been the fact that they were new replacing old.
 

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Discussion Starter · #17 · (Edited)
Things you’ll need for removal: Ratchet, extension, and spark plug socket. It’s a socket with a rubber in it.
How to remove: Unscrew the screw that is holding the coil down. Pull up and remove the coil. Then, stick the extension and socket that are connected to the ratchet into the hole to seat the socket around the spark plug. Once the socket is aligned properly and seated, turn the ratchet to the left. Go slow at first. If they haven’t been changed in awhile spray some penetrating oil in the holes first and let it sit awhile before you try to remove them. When you tighten them down get them tight, but don’t be the Incredible Hulk. Once they stop getting tighter stop.
I guess it was the whole removing the coil thing that threw me. Plus getting my eyes to focus on the video was an issue. Anyway, having dedicated coils on each spark plug was new to me instead of just having one ignition coil with a distributor. Kinda like some vehicles not having a transmission oil dipstick is new to me. Kinda weird having to pump the transmission oil back into the car. Obviously I have some catching up to do. My understanding is that you have to avoid forcing a feeler gauge into these platinum and iridium plugs also.
 

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I guess it was the whole removing the coil thing that threw me. Plus getting my eyes to focus on the video was an issue. Anyway, having dedicated coils on each spark plug was new to me instead of just having one ignition coil with a distributor. Kinda like some vehicles not having a transmission oil dipstick is new to me (like my 2014 Xterra). Kinda weird having to pump the transmission oil back into the car. Obviously I have some catching up to do. My understanding is that you have to avoid forcing a feeler gauge into these platinum and iridium plugs also.
I think you’re sweating the feeler gauge rubbing the tip too much. Surely the conditions they are under when in use in the vehicle is worse than a rub with a feeler.
 

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It's my understanding that the 99-04 stock plugs are platinum. I've heard that they have a life span of about 100,000 miles but iridium lasts 200,000 miles. I was wondering if it's worth replacing the platinum with iridium? I'm not sure if I'll still have my 02 that long. It's been a long time since I changed a spark plug and I've heard that it's a bit different now.
Hi...the iridium plugs will work fine.Motorcraft sells them for your car/year
 
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