What Are The Best Spark Plugs To Use?

[LMHmedchem]

The original plugs are crap. Platinum are crap, double platinum is...well...double the crap. Go with Autolite Iridiums (XP103.)

RockAuto lists both Autolite XP103 and XP104 for the correct Ford part. If you search through their part catalog, Ford > 2002 > Explorer > 4.6V8 > Ignition > Spark Plugs it gives XP104 as the part number. The XP103 part lists Ford up to 2013 as compatible, though that doesn't seem likely.

Is the XP104 part what I need because I have the V8 where XP103 is for the V6, or isn't there a difference?

LMHmedchem

 

[swshawaii]

Where are you seeing Autolite XP103 on RA for your 2002 4.6? XP104 is the correct Autolite XP plug for your vehicle.
https://www.rockauto.com/catalog/ra....6L+V8+Ignition+Spark+Plug&blanktemplate=true

XP103 is a very common plug used on many different makes and engines and is one heat range colder.
Amazon shows 2301 fitments but not yours.
http://www.amazon.com/gp/product/co...Model=Explorer|663&Year=2002|2002&vehicleId=1

See Autolite Training Manual link in post #5 .

 

[Number4]

The XP103 was being discussed here because the original post involved the V6.
Go with what is shown for the 4.6l V8.

 

[swshawaii]

The XP103 was being discussed here because the original post involved the V6.
Go with what is shown for the 4.6l V8.

Got it. Anti seize or not?

 

[Number4]

Got it. Anti seize or not?

I hear they use JB Weld in Hawaii, though I personally wouldn't recommend it. :mattmoon:

 

[LMHmedchem]

The XP103 was being discussed here because the original post involved the V6.
Go with what is shown for the 4.6l V8.

For some reason I was laboring under the impression that the original poster had the same engine, so I was surprised to see a different part number come up.

Does it make sense to replace the plug wires at the same time? I'm not sure when they were replaced last. Can someone recommend the right anti-seize for the threads and dielectric grease for the wire boots? I always get lost in the grease aisle, who knew how many different products there were for ruining your clothes.

I'm still not smart enough to work with gloves on, I swear I go through as much orange hand cleaner as I do gasoline.

LMHmedchem

 

[Number4]

Do not use anti seize. The heads are aluminum, not iron. The plugs you'll notice are 'silver,' they have a built in anti seize.

The torque is only 13lbs. Anti seize will reduce the friction and cause over torquing. The result of this could easily be a blown spark plug into your hood.

Dielectric grease is dielectric grease, buy it in what ever quantity you'd like.

I buy the black Raven rubber gloves. They are durable and usually last an entire repair.

No wires, coils on plugs (cop.). You can buy the rubber boot piece that connects the coils to the plugs.

 

[TechGuru]

I'm still not smart enough to work with gloves on, I swear I go through as much orange hand cleaner as I do gasoline.

Don't! I use Classic Blue DAWN most of the time and for the tough spots I use a bar of LAVA.

 

[LMHmedchem]

I ordered 8 of the Autolite XP104 Iridium Plugs at $4.50 each from RockAuto. I also got a tube of Prematex Dielectric Grease. My understanding is that you only need a very small amount in the boot. Is there a video floating around about this or is it too straightforward to bother making a video for.

LMHmedchem

 

[LMHmedchem]

Is there a video anywhere that shows how to do the plugs on the passengers side of the 4.6L v8? I have seen a number of vids, but they always just show the drivers side which is easy. I would like to see exactly what I need to remove from the passengers side to get to the coils as opposed to just pulling stuff off and hoping I get lucky. I would really appreciate it if anyone knows of a link to a good vid.

My back isn't too good and I can't work on this kind of thing for all that long at one sitting. Is it a problem if I just change some of the plugs and then go back to change the rest later? Will that throw off the ignition sequence?

Thanks for the help.

LMHmedchem

 

[Number4]

Just remove the air intake hose and you should have all the access you need.

Once you remove the coil bolts, they'll flex at the boot and come right out.
Just make sure you have compressed air to blow out the debris (sand/grit) that's collected in the spark plug wells.

The V8 plugs are actually really simple to do.

 

[LMHmedchem]

The V8 plugs are actually really simple to do.

Thanks, I will give this a try over the next few days. If I remember right, the air intake is just a hose clamp. Do I have that right?

Also, I have read that I should spray a bit of PB into the spark plug wells after removing and dirt and before trying to loosen them. Is that a good idea? I have no idea how long these plugs have been in place and I would rather not break one trying to get it out.

LMHmedchem

 

[Number4]

Undo the little hose at the intake hose, coming from the drivers side valve cover.
Undo the intake hose from the throttle body.
Undo the air filter box clamps and remove lid and hose assembly. Set aside, electrical wires will limit how far it moves. Roll it over toward the front of the engine.

You can spray the plugs with some penetrant, but I'm of the opinion that stuck plugs were changed once and over tightened when re-installed.

The heads are aluminum, so there shouldn't be any rust issues bonding the plugs to it.
Once read where someone used a torque wrench to remove them. If it took too much torque (don't recall the amount, 30lbs?) to turn, they soak with penetrant and waited.

I've removed two sets, one had 150k miles on them. Never had an issue.

Those wells are full of crap though and it's hardened over time. So as you back out a plug, it'll break crud loose. Just blast with air or vacuum out as you go. Use an inspection mirror to see if needed.

Biggest thing, torque to spec when installing. It's something like 13 lbs. if you guess, you'll over tighten.
Also, you'll notice the new plugs have 'grey' or 'silver' color to the threads. This is a pretreatment of anti seize. Do NOT add anti seize or you'll end up over tightening the new plugs.

I may have already said all this in an earlier post, but it's worth repeating.

Again, a lot of threads or Haynes have made this out to be a difficult job, some even saying to remove the fuel rail. The coil boots will flex allowing the coils to come right out. This is an easy R&R job.

 

[apenland01]

And use wobble extensions. They are invaluable when you can't quite line up on the plug or the coil pack bolt. I used the Autolite XP104 plugs and have been happy with them. Only one plug came out of the box at .054, the rest were all over/under gapped, so not "pre-gapped" as stated on the box.

 

[LMHmedchem]

And use wobble extensions. They are invaluable when you can't quite line up on the plug or the coil pack bolt.

I did the replacement today and everything went fine. It took about 2 hours altogether. It was nice out today so I wanted to get it done before it starts to be not nice (which it will shortly).

I was able to disconnect the wire from the air filter hose assembly and remove it completely. The is just a little quick connector there near the filter box.

I did the following.
1. disconnect the negative battery terminal
2. spray all the coil retaining bolts with PB (some were quite rusted).
3. remove the air filter hose assembly and set aside
4. confirm that I could loosen the coil retaining bolts
- as suggested, the wobble extensions were very helpful for some of these.
- a small flashlight was also very necessary

Once I was sure I could loosen all of the coils, I went ahead with the replacement.

5. pull each coil and boot
- I disconnected the wire after pulling the coil for most of them, it was hard to get the wire un-clipped before pulling the coil off of the plug.
- two of the boots came off and remained in the hole. These were removed with a pair of needle nose.
6. blow out each spark plug hole with an air compressor and vacuum
7. spray a small amount of PB into each spark plug hole
8. set a clicker to 20lb and use a spark plug socket and wobble extension to break each plug free.
- I stayed with 20lbs on the clicker because I wanted to be conservative. It was nice to have the longer handle as well. It took some effort with some of the plugs but the clicker never engaged.

Again, I made sure that all 8 plugs would break loose before completely removing any of them.

9. after breaking loose, turn each plug a 1/4 turn and spray some carb cleaner down around the socket.
10. remove each plug and discard.

Looking into each plug hole, There was still some carbon junk left after the plug was removed. I was concerned about this getting into the threads so I sprayed a bit more carb cleaner into each hole before installing the new plug. This cleaned thing up pretty well but I wouldn't want to over do it on this.

11. Remove the rubber retaining boot from the plug socket and install the new plugs.
- I was a bit concerned that I wouldn't get the socket off of the new plug and out of the hole if I left the retaining boot in the socket, not sure if this is a common problem or not.
- use just the plug socket and a straight extension (not wobble) to get the new plugs started. This was the hardest part in some ways. I tried to hold the extension very straight and turn it gently to let the threads catch. If I felt resistance, I backed the plug back out and tried again. Once the plug got started, I visually inspected to make sure the plug looked straight. I was careful to make sure that the plug would go all the way down without much resistance. I visually confirmed that the plug had seated all the way to the bottom of the hole. I found this to take about 15 turns.
13. set a clicker to 13lb and tighten each plug.
14. put a small amount of dielectric grease into the mouth of each coil boot
- I spread the grease around the inside edge with a small screwdriver. I wanted to make sure that the grease made a good seal around the entire boot. I kept the grease out of the center of the coil for the most part.
15. reinstall each boot, coil retention screw, and wire.
16. reconnect the battery

It started right up. It did run a bit rough for a second or so and I guess the it the carb cleaner and PB getting burnt out. It runs very nicely now as far as I can tell.

I used the Autolite XP104 plugs and have been happy with them. Only one plug came out of the box at .054, the rest were all over/under gapped, so not "pre-gapped" as stated on the box.

I didn't check the gap on the new plugs and this may have been a mistake. I used the same Autolite XP104 Iridium Plugs from RockAuto and assumed they would have the correct gap as indicated by the specs. I am a bit reluctant to pull them again to check. Is the fact that the engine is running well mean that the gaps are more or less correct? If the gaps are off, will that show up in the software if I connect my computer to the obd? In short, is it worth pulling the plugs to check even if the engine is running well?

I have been looking a bit for odb software that I can use to tune the engine. Most of the software documentation is a bit unclear as to if it can be used to do a tuneup or not. Is there something that users here would recommend for that?

LMHmedchem

 

[apenland01]

I'm just OCD about that kind of thing, so I always check the gap on every plug before I put them in. Autolite says they don't need gapping, but they get bumped in transit from the factory, so inevitably most are under. Some of mine were at like .048. that's too narrow for my taste on the 4.6L V8. If it is running fine, you are probably okay. I wouldn't pull them unless you think it isn't running smoothly or you're just OCD too.....

If you decide to pull them to check the gap, just make sure you don't touch the fine wire when changing the gap, since it is quite fragile.

 

[LMHmedchem]

If you decide to pull them to check the gap, just make sure you don't touch the fine wire when changing the gap, since it is quite fragile.

How do you increase the gap size without disturbing the fine wire? Do you use a pair of pliers to bend up the ground electrode? None of the gaping methods I have seen look all that "precision", which is odd since you are trying to achieve a gap accurate to 1/10 mm.

Seems like it would be easier to change the packaging and keep them to manufactured specs.

LMHmedchem

 

[apenland01]

I have a round plug gapper that has a hole in it. You slide the top into the hole and it doesn't touch the fine wire. Then you just give it slight pressure and recheck. I've never used pliers or anything, just my plug gapper. Its not a problem to touch the fine wire, just make sure it isn't getting any pressure when you adjust the gap.

Any auto parts store will have a plug gapper for $1 or so that will have the hole, so you can adjust the gap without putting any pressure on the electrode fine wire. If its under gapped, just use the plug gapper. If its over gapped, gently tap it on a hard surface once or twice and recheck.

 

[lincolnshibuya]

when I did the plugs (even motorcraft) 3 out of 6/8 usually is over gapped.

this pic

 

[swshawaii]

ALWAYS check the gap carefully regardless of what the manufacturer says. According to Amazon,
Autolite XP104 fits 3094 applications, the first being Audi at .032" and the range goes up to .054".
http://www.amazon.com/gp/product/compatibility-chart/B000ET5TC6/ref=au_pf_dp_chart

From Autolite's web site FAQ:

Q: Do Autolite® spark plugs come pre-gapped from the factory?

Autolite® and all spark plug manufacturers offer spark plugs pre-gapped in the most popular gap sizes.

Because of the many gap sizes required, no one offers spark plugs properly gapped for every application.
Gapping has always been the job of the installer. You can be sure that the Autolite® spark plug recommended for your application has been engineered to meet the requirements of your engine, and that the gap can easily be adjusted as required.

http://www.autolite.com/product-information/faqs.aspx#all