Spark Plugs

[DC]

It's time to change the plugs in my TJ. I know this might be akin to a Ford versus Chevy thing, but what's the latest and greatest in terms of plugs for the I-6?

[H8PVMNT00]

Honestly, imo, I have been running the Champion truck plugs for some time now and they have been really great compared to Bosch plugs that i used to run. Even after having the Jeep sit for some time(5 mos to be exact) they still turned over, and ran great with the first turn key...i believe i picked them for for 2$ and some change. This is just my opinion!

[TObject]

Champion 4412 - 6 cyl TJ Spark Plugs. Found the good thing, and sticking to it.

[DC]

Originally posted by TObject
Champion 4412 - 6 cyl TJ Spark Plugs. Found the good thing, and sticking to it.

Sergey,

So, are the Champion 4412 plugs the recommended stock plugs for the 6 cylinder engine, the Champion "truck plugs" that H8PVMNT00 referenced, or something else? Please let me know.

Thanks,
Don

[H8PVMNT00]

Dc,
The plugs that i refered to which were "truck plugs" are the same ones that T0bject mentioned. FOr your info here is the link :
http://www.championsparkplugs.com/re...=4412&x=21&y=2

All i did was enter the part # 4412 and the description you see when you go to the link comes up listed at the Champion Truck Plugs..I hope this helps.. Vic

[TObject]

Originally posted by DC
So, are the Champion 4412 plugs the recommended stock plugs for the 6 cylinder engine, the Champion "truck plugs" that H8PVMNT00 referenced, or something else? Please let me know.

It's what H8PVMNT00 recommended. They are not the same number as the stock plugs, but they are the same size. Many aftermarket plugs do not go deep enough, these do.

[Jerry Bransford]

I ran Champion's Truck plugs until they wore out and while they ran well, they didn't seem to perform any better to me than the Autolite platinum plugs they replaced. And because the Autolites have a 2X to 3X longer life due to their platinum coating, I went back to them and the Jeep runs equally well on them. When I last pulled them at 60K miles, they still looked brand-new.

If you want to try platinum plugs, do know that newer TJ 4.0L engines without distributors should ONLY run either conventional non-platinum (like the Champion Truck plug) or plugs with platinum on both sides of the gap which is called "double tipped" platinum. Using plugs with platinum on just one side of the gap (called "single-tipped") causes hard to diagnose occasional rough-running engine problems for distributorless ignition systems.

For older TJs that have distributors, you can run any style platinum plug, single or double-tipped, without problem, or non-platinum plugs. However, there's no benefit to paying extra for the double-tipped platinum plugs in these earlier 4.0L engines since only one side of the gap benefits from the platinum coating in terms of resistance to wear.

You can't go wrong with Champion's Truck plug, but because it needs to be changed 2-3X as often as Autolite's Platinum plug, I prefer the Autolite plug. As I said, I can't tell the difference in how they make my engine run... it's just that in my personal experience, one outlasts the other by a substantial margin. And I'd rather be doing other stuff than changing spark plugs 2-3X as often.

[Robert J. Yates]

The service interval for the ignition is 30k so I'm not sure why I would need plugs that last 2-3x longer than the 4412's

[Jeff Weston]

Originally posted by Robert J. Yates
The service interval for the ignition is 30k so I'm not sure why I would need plugs that last 2-3x longer than the 4412's

Yeah, at the current rate, my truck plugs will last me 10 years!

I think Jerry's Jeep is still a daily driver so that may be his motive on the platinums?

[Jerry Bransford]

Originally posted by Jeff Weston
I think Jerry's Jeep is still a daily driver so that may be his motive on the platinums?

Yep, daily driver it is. My #1 spark plug is a big enough PITA to get to through the a/c bracket that any reduction in the need to change them is a huge plus in my book. I'm getting old is all.

[Stu Olson]

I'm on my 2nd set of Champion truck plugs.....change them every 30K miles.

Peronsally, I don't like leaving plugs in the head longer than 30K miles. I've seen them break while attempting to remove them....not my idea of fun. Was it because they were in too long? Don't know....don't care.....mine come out every 30K miles. It costs about $15 to change the plugs.....I'm not going to fight a broken one because of a couple of dollars.

I also don't believe in removing a plug and then putting it back in. The crush gasket on the plug is designed to crush once.

[Robert J. Yates]

Originally posted by Jerry Bransford
Yep, daily driver it is. My #1 spark plug is a big enough PITA to get to through the a/c bracket that any reduction in the need to change them is a huge plus in my book. I'm getting old is all.

Come on Jerry - I have the same issue and a swivel and an extension is all it takes. That plug should only be a PITA for noobs

[DC]

Thanks everyone. I will be going with the Champion 4412 truck plugs. And from what Sergey mentioned (about them being a "deeper" plug), I assume this means they are a "hotter" plug than the stock or aftermarket replacement plugs. In any regard, is everyone still using the same stock gap of 0.035" with the truck plugs?

[mrblaine]

Originally posted by DC
Thanks everyone. I will be going with the Champion 4412 truck plugs. And from what Sergey mentioned (about them being a "deeper" plug), I assume this means they are a "hotter" plug than the stock or aftermarket replacement plugs. In any regard, is everyone still using the same stock gap of 0.035" with the truck plugs?

NO, they are not a hotter plug. By deeper, he means that they extend into the combustion chamber the same depth as stock.

If you compare some plugs for the 4 liter application at the parts store, some of them have a fairly short nose on them.

[Jerry Bransford]

Originally posted by Robert J. Yates
Come on Jerry - I have the same issue and a swivel and an extension is all it takes. That plug should only be a PITA for noobs

You're right Robert, it's not that big of a PITA once you figure that out... but I sure learned to love knowing my plugs would last so long. A longer plug change interval is never a bad thing in my book.

I was taken by a revelation on platinum plugs when I owned my Lexus LS400. When I asked the service guy how long I should wait before changing its plugs, I about fell over when he said they were good for 100K miles. When I did finally change them at that magic number, they were actually still in pretty good shape. Pretty amazing to a guy like me that started off with ignitions with points and condensers where the plugs typically lasted maybe 15K miles. That 100K mile interval on the Lexus kind of got me over the hump on just how good platinum plugs can be.

[Robert J. Yates]

Thats all fine and dandy Jerry but you still have a 30k service interval on the rest of the parts (plug wires, rotor and cap). If you have to get in there for those, might as well do the plugs too as it adds about 15 minutes to the job.

[seajeeper]

30K? I guess I better get on this and at least LOOK at these. I changed the stock plugs at about 12K (and broke 5 out of 6) 6 years ago. I haven't touched the ignition since. I currently have 65K on stock wires, cap, rotor, and 50+K on the autolite regular old plugs.

I sure hope you haven't jinxed me Robert!

[Tumbleweed]

I have 69K on the stock plugs-original ones. Picked up a set today to get changed before my summer trip. Thanks for the reminder.

[mrblaine]

So, I'm over helping a top competitor mount some tires for his buggy and he shows me his new double platinum plugs he's about to swap in. A quick comparison shows them to be about 300 thousandths shorter than the ones that came out.

Since the engine convertor told him the part number to use, we decided to try them in his Ecotec motor out of a Saturn.

Gap and install and the motor won't idle without missing and has a pronounced cough at partial throttle and you can't give it amount of throttle without it seriously stumbling.

Swap the old plugs back in and it runs perfectly.

[DsrtJeeper]

As Blaine and others have found out; there is alot of snake oil in the plug business. Two things have shown any promise as far as plug mods...A "V" gapped electrode and indexing plugs. The gains are by no means huge, but something that should be reserved when all else is tweaked. Chances are that your manufacturer has done their homework on plugs for a very clean burn. This is one of those areas such as oil additives where people try to out engineer the original design.

Stick with what has worked from day one; folks.

[blkTJ]

I recently did my plugs, wires, cap and rotor. used the recomended champion TJ replacement part. It had been about 36k miles and it was interesting to see that the gap on the old plugs had burned to about .045. just a FWIW.

[quadna71]

over the past few years i've swapped 4412's in my tj, my first xj, my first tj, and her dad's xj. but - what about her tj with the 4 cyl? i've heard that it's pretty much the 4.0 with two cylinders lopped off...so would that be a good spark plug for it? ('01 tj)
chris

[Robert J. Yates]

Originally posted by seajeeper
30K? I guess I better get on this and at least LOOK at these. I changed the stock plugs at about 12K (and broke 5 out of 6) 6 years ago. I haven't touched the ignition since. I currently have 65K on stock wires, cap, rotor, and 50+K on the autolite regular old plugs.

I sure hope you haven't jinxed me Robert!

I hope not too but I can't believe some of you guys and your service intervals. Maybe its just me being paranoid but there are plenty of things to go wrong on a rig as it is (out in the middle of nowhere) to not do basic ignition as well as other maintenance.

While not plug related, its still a good example of what I am talking about. 2 years ago, I had my Jeep start running like crap and then simply shut itself off while negotiating the exit on Clawhammer. Great, now I am on the winch and nothing would get it started. We assumed that pointed to the CPS which was still the original unit with 60k on it. Pulled out the spare and still nothing. Swapped in a TPS (to replace the stocker) and still nothing.

Now, I was to far into the trail to have enough battery power to winch myself out and the exit of Claw is not one where you can move alot of vehicles around and get someone into a position to strap a rig out so things were looking a bit grim. Thats when Scott Hill noticed that my fuel pump was not making any noise when I turned the key to start. Turned out to be a simple 25 cent 20amp fuse causing the problem. I can't for the life of me figure out why that fuse blew and its never happened since but like I said, there is plenty of crap to go wrong on a rig that can come out of nowhere not to do maintenance.

[DsrtJeeper]

Originally posted by Robert J. Yates
I hope not too but I can't believe some of you guys and your service intervals. Maybe its just me being paranoid but there are plenty of things to go wrong on a rig as it is (out in the middle of nowhere) to not do basic ignition as well as other maintenance.

While not plug related, its still a good example of what I am talking about. 2 years ago, I had my Jeep start running like crap and then simply shut itself off while negotiating the exit on Clawhammer. Great, now I am on the winch and nothing would get it started. We assumed that pointed to the CPS which was still the original unit with 60k on it. Pulled out the spare and still nothing. Swapped in a TPS (to replace the stocker) and still nothing.

Now, I was to far into the trail to have enough battery power to winch myself out and the exit of Claw is not one where you can move alot of vehicles around and get someone into a position to strap a rig out so things were looking a bit grim. Thats when Scott Hill noticed that my fuel pump was not making any noise when I turned the key to start. Turned out to be a simple 25 cent 20amp fuse causing the problem. I can't for the life of me figure out why that fuse blew and its never happened since but like I said, there is plenty of crap to go wrong on a rig that can come out of nowhere not to do maintenance.

Robert;
What preventative maintenance would you have performed to prevent the above?

[Robert J. Yates]

None that I hadn't already done - I at least knew what not to look at Eric

[DsrtJeeper]

Originally posted by Robert J. Yates
None that I hadn't already done - I at least knew what not to look at Eric

According to the masses; we will live a very short life anyways due to the running of aluminum steering parts and welded cast knuckles. I guess spark plugs are the least of our worries.

Oh, and i've been informed that aluminum skids just dig into the rocks and stop you dead.

[Robert J. Yates]

Originally posted by DsrtJeeper
I guess spark plugs are the least of our worries.

....for some people apparently

[DsrtJeeper]

Originally posted by Robert J. Yates
....for some people apparently

Hey now! Quit taking things outta context! I maintain my vehicle very well. Of course; it does only have 20,000 miles on it.
Should I change the oil yet?

[Stu Olson]

Originally posted by DsrtJeeper
Of course; it does only have 20,000 miles on it.
Should I change the oil yet?

No reason to just yet.....might as well wait until you have 65K miles on the ignition components and change it when you do that.....no use opening the hood too often to do maintenance.....the hinges might wear out or something.

[Robert J. Yates]

Yea, just wait for it to crap out while on the trail and do your maintenance then. Your wheeling buddies won't mind in the least