HOW TO: Change Spark-Plugs

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profdlp

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Pep boys has the wrong spark plug gap listed for the 2004 jeep liberty 3.7L and tried offering me up 0.035 OR 0.044 to the point I second guessed myself and went out to my car to double check. And yup, 0.040 right there under the hood.

Maybe the Pepsters want you to average them out.

.035 + .044 = .079 / 2 = .0395 :icon_lol:
 

mohamer

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Thank you

Hey, I am new to the forum, just got a 06 Liberty. I just changed the plugs on it yesterday and I wanted to thank the forum for having this post to give me some insight to problems before I did the job.
I started with No. 6, relocated the coolant tank out of the way and the snorkle, I had no problems with any of the plugs, all went very well.
The plugs in it were NGK ZFR6F 11G which are Cooper/Nickle plugs.
I do not know how many miles they had on them but they are toast!!!
The center electrodes are almost even with the ceramic, about 80 thousanths gap, really worn out.
I installed NGK ZRF6FIX-11 which is the Iridium plug, it is about all I will use, they are good for 100,000 miles plus. I put antiseize on them and everything looks good.
I also changed the T-Case oil yesterday, it was old.

Thanks
John in Joplin kb0ou :icon_lol:
 

tommudd

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Hey, I am new to the forum, just got a 06 Liberty. I just changed the plugs on it yesterday and I wanted to thank the forum for having this post to give me some insight to problems before I did the job.
I started with No. 6, relocated the coolant tank out of the way and the snorkle, I had no problems with any of the plugs, all went very well.
The plugs in it were NGK ZFR6F 11G which are Cooper/Nickle plugs.
I do not know how many miles they had on them but they are toast!!!
The center electrodes are almost even with the ceramic, about 80 thousanths gap, really worn out.
I installed NGK ZRF6FIX-11 which is the Iridium plug, it is about all I will use, they are good for 100,000 miles plus. I put antiseize on them and everything looks good.
I also changed the T-Case oil yesterday, it was old.

Thanks
John in Joplin kb0ou :icon_lol:

well all I can say is good luck, never make it 100,000 miles
 

mohamer

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Ix plugs

tommudd,
Have you ever run Iridium plugs? It seems maybe you have not. I just changed the plugs on our Prius (by Toyota). The Iridium plugs in it had 120,000 miles on them and they looked very good. Very little wear at all, I could have put them back in and run them another 100k very easily, but I had new ones to put in so I just put them in storage (part Irish, hard to throw anything away).
I threw the plugs away that I took out of the Jeep.

By the way I have also run IX plugs on motorcycles and a lot of other vehicles and have never had a problem out of them. :gr_grin:
 

dude1116

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tommudd,
Have you ever run Iridium plugs? It seems maybe you have not. I just changed the plugs on our Prius (by Toyota). The Iridium plugs in it had 120,000 miles on them and they looked very good. Very little wear at all, I could have put them back in and run them another 100k very easily, but I had new ones to put in so I just put them in storage (part Irish, hard to throw anything away).
I threw the plugs away that I took out of the Jeep.

By the way I have also run IX plugs on motorcycles and a lot of other vehicles and have never had a problem out of them. :gr_grin:

Prius? Get the f**k out.

Completely different vehicles. Comparing apples and oranges. Have fun getting misfires. Put coppers in there if you decide to run what the engine is designed for.
 

tommudd

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tommudd,
Have you ever run Iridium plugs? It seems maybe you have not. I just changed the plugs on our Prius (by Toyota). The Iridium plugs in it had 120,000 miles on them and they looked very good. Very little wear at all, I could have put them back in and run them another 100k very easily, but I had new ones to put in so I just put them in storage (part Irish, hard to throw anything away).
I threw the plugs away that I took out of the Jeep.

By the way I have also run IX plugs on motorcycles and a lot of other vehicles and have never had a problem out of them. :gr_grin:

I have removed a few sets for others and tossed them
But what you seem to foegt is the 3.7 was designed to run coppers, its an older style engine that does not respond well to these new fangled plugs
Now that disco car may but not the 3.7 in a KJ
 

ouroboros

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Why would you break something that don't need fixin'... ******** prius owners... Chrysler specified right under the hood the exact brand, make and model spark plug that needs to be in the KJ.
 

tigerKJ

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What I found interesting was that I asked for a quote, from a repair shop, on getting my plugs changed. They said with platinum plugs and labor $230 - ouch!

So after looking at this thread and running to the auto parts store I picked up the NGK ZFR6F-11G plugs at less than $2 each with tax and installed them in under 2 hours. I took my time to remove the air resonator my '02 has. This made it easier to get the passenger side plugs out and back in.

I understand for some engines platinum and iridium plugs are best, but everyone here has mentioned that the standard copper plugs are best for this engine.

Thanks for saving me $212 :party36:
 

ouroboros

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What I found interesting was that I asked for a quote, from a repair shop, on getting my plugs changed. They said with platinum plugs and labor $230 - ouch!

So after looking at this thread and running to the auto parts store I picked up the NGK ZFR6F-11G plugs at less than $2 each with tax and installed them in under 2 hours. I took my time to remove the air resonator my '02 has. This made it easier to get the passenger side plugs out and back in.

I understand for some engines platinum and iridium plugs are best, but everyone here has mentioned that the standard copper plugs are best for this engine.

Thanks for saving me $212 :party36:

Should have told them to shove those platinum plugs up their ass. Were they JUST changing plugs or was there ignition coils added in? I can honestly understand the high price on labor if they charged by book time. Most guys don't work hourly they only get a percentage on each job.
 

tigerKJ

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Yeah, the price they quoted was just plugs and labor. After reading this thread, and WITHOUT the apartment complex management watching, I installed new plugs myself.

This is a helpful forum! Thanks everyone!
 

mohamer

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Running Very Good

Hey,
You guys are really funny, my Iridium plugs are doing just fine thanks..:icon_twisted:
Just check my gas mileage, on 3/4 tank running 1/2 in town and 1/2 on hiway, I got over 20 mpg, and a lot of the hiway was very hilly (ozarks).

You guys can stay in the Copper age if ya want, I will run IX plugs, and have in my motorcycle (1979 model) and several other vehicles (including Prius).

I really appreciate the personal attacks just because I happen to have a Prius.
That really make the forum look good!! :thumbsdown:

Remember, I posted a THANK YOU for the help and just happened to mention the P word, get a life guys!!

If all the people are this backward on the forum I don't think you have much future....:gr_grin:

Y'all have fun now!!! :party52:

John in Joplin kb0ou
 
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nullptr

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Y'all have fun now!!! :party52:

John in Joplin kb0ou

Someone has thin skin. :happy175:

Good luck with those plugs, I've not run any in mine, but I had bad experience with them in my old BMW. Put the new plugs in, and within 3 months it was misfiring and throwing CELs like crazy. Ripped them out and tossed some coppers in, and it ran great after that. :shrug:

Personally I think it has more to do with what the ignition system was designed to work with. My BMW and this Jeep were designed with copper plugs in mind, which has a completely different resistance to electricity than Iridium or Platinum. I would be surprised if those plugs make it 100k miles, since the ignition coils aren't designed for them.
 

ouroboros

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Someone has thin skin. :happy175:

Good luck with those plugs, I've not run any in mine, but I had bad experience with them in my old BMW. Put the new plugs in, and within 3 months it was misfiring and throwing CELs like crazy. Ripped them out and tossed some coppers in, and it ran great after that. :shrug:

Personally I think it has more to do with what the ignition system was designed to work with. My BMW and this Jeep were designed with copper plugs in mind, which has a completely different resistance to electricity than Iridium or Platinum. I would be surprised if those plugs make it 100k miles, since the ignition coils aren't designed for them.

Not only what you said, but copper is the most conductive of all the different types of spark plugs. Iridium and platinum plugs are more likely to overheat also, so.... Stick with what the manufacturer says when it comes to your ignition system :gr_grin: A lot of the later model vehicles out today actually come with OE platinum plugs, but not KJ's. It says in the damn engine bay what you're supposed to use anyway! :happy175:
 

dude1116

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Hey,
You guys are really funny, my Iridium plugs are doing just fine thanks..:icon_twisted:
Just check my gas mileage, on 3/4 tank running 1/2 in town and 1/2 on hiway, I got over 20 mpg, and a lot of the hiway was very hilly (ozarks).

You guys can stay in the Copper age if ya want, I will run IX plugs, and have in my motorcycle (1979 model) and several other vehicles (including Prius).

I really appreciate the personal attacks just because I happen to have a Prius.
That really make the forum look good!! :thumbsdown:

Remember, I posted a THANK YOU for the help and just happened to mention the P word, get a life guys!!

If all the people are this backward on the forum I don't think you have much future....:gr_grin:

Y'all have fun now!!! :party52:

John in Joplin kb0ou

:Bye:

I was saying that a Prius and a KJ are completely different vehicles. Glad to hear your properly maintained KJ is still getting 20MPGs! I was getting the same and more prior to the lift and tires. Using copper plugs. Now I'm getting 17s rolling on LT265/70s

Gotta get so defensive huh?
 

mohamer

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Kj and prius coil pac

Howdy Again,
It is interesting to note that the coil pac on the Prius and the coil pac on the KJ are almost copies of each other.

I would like for one of you to tell me the difference in the ignition system like in the Prius that is made for Iridium Plugs (they come from the factory that way) and the ignition system of the KJ.

My Prius is a 2005 the KJ I just purchased is a 2006 and the coils are almost identical.

Also what is the difference in resistance from a Iridium Plug made for a KJ or a Copper Plug made for a KJ??? I would love to know. :blah:

Also, why is it just fine to jack up a KJ, put big tires and wheels on it etc. but it is a terrible thing to put a spark plug that is a little different in the engine?? :emotions34:

No, don't think I am very thin skinned, I actually think you guy are hilarious and small brained.... :gr_grin:

NO MISSES on the plugs!!!! :happy175:

Again, Thanks.

John IN Joplin kb0ou
 

dude1116

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Howdy Again,
It is interesting to note that the coil pac on the Prius and the coil pac on the KJ are almost copies of each other.

I would like for one of you to tell me the difference in the ignition system like in the Prius that is made for Iridium Plugs (they come from the factory that way) and the ignition system of the KJ.

My Prius is a 2005 the KJ I just purchased is a 2006 and the coils are almost identical.

Also what is the difference in resistance from a Iridium Plug made for a KJ or a Copper Plug made for a KJ??? I would love to know. :blah:

Also, why is it just fine to jack up a KJ, put big tires and wheels on it etc. but it is a terrible thing to put a spark plug that is a little different in the engine?? :emotions34:

No, don't think I am very thin skinned, I actually think you guy are hilarious and small brained.... :gr_grin:

NO MISSES on the plugs!!!! :happy175:

Again, Thanks.

John IN Joplin kb0ou

We're just telling you what we've found from EXPERIENCE. Which happens to be what ANY automotive professional will tell you - go with what the engine is designed to run.

I don't know why you think ANYTHING on the Prius is remotely similar to the KJ. Have you taken apart the coil packs and analyzed coil resistance and heat? Have you analyzed the way the fuel injectors work in the Prius vs in the KJ? Didn't think so.

The difference between Copper and Iridium is plain and simple: Copper conducts electricity better (which equates to a better spark) and Iridium are more likely to overheat, causing damage to the plug and even more. If the Prius was designed to run with Iridium, then it was not designed to run at a temperature to burn them out.

We're not calling you an idiot or any of the likes. We're trying to save you frustration and trouble down the line. This has nothing to do with the sense of a lift and tires.

Small brained? F**king child.
 
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ouroboros

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Because you can judge a book by it's cover... Ahem, excuse me an ignition coil by it's casing. :happy175:
 

tommudd

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When you go to the parts store they ask what you drive etc and then you are forced to tell them what you want , copper spark plugs or those of another type? You can find spark plugs in a variety of ones, including aluminum spark plugs, iridium plugs, platinum and more. Copper core spark plugs are still the most commonly seen, however, and many people agree that they are the best. However, the advertising that accompanies the different types of spark plugs is potentially misleading, so it's important to recognize the real difference between the spark plugs in question.
The metal in a spark plug serves a single basic purpose: to channel the energy from the plug wire through the spark plug so that it can be forced to the engine block in the form of a spark. Therefore, any metal that conducts electricity at all could potentially be used for a spark plug. The metal should also not get too hot; one of the main problems with some metals is that they overheat quickly, causing the electric charge itself to be compromised and the spark plug to not operate as smoothly.

Copper spark plugs are generally considered to have the best performance of any spark plug type. This is potentially different from what advertising companies suggest, but the other metals are, unfortunately, not as conductive in general as copper is.
Platinum and iridium plugs are more likely to overheat, which causes damage to the plug components and can compromise the delivery of the spark to the engine block.
 

tommudd

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Platinum and Iridium plugs perform at a lower level than copper spark plugs, because they are less conductive and they tend to overheat. However, the overall longevity of these two types of metal is better than copper plugs. In reality, copper has the best performance of all three[/B. Platinum has good longevity and the worst performance. Iridium has good longevity and a performance that is decent, which is why iridium plugs tend to be more expensive than any other type. Still, the difference between these plugs in terms of overall quality is minimal, as there is a trade off for each.
Most copper plugs need to be changed every 20,000 miles or so. Platinum and iridium plugs can often go for twice that before they require changing, but the overall performance will not be as good and you may have to deal with overheating of the plugs. This is potentially not worth the added cost of both platinum and iridium spark plugs, although the decision will depend upon your preference.

PLUS they use the iridium's in cars like Prius's due to most of those owners only know enough to get in and find drive and move forward, they are not a thinking mans car or one that many own that even could find the spark plugs .
 
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