Changed my plugs after 38k (PICS)

[johnny_vitz]

NGK makes a quality plug for a good price. The only thing wrong with denso's most of the time (especially iridiums) is the price. The quality is there, they just want too much for them.

Wonder how the difference would be noticed if at all on a boosted motor...

You're better off using copper plugs when boosting

[Yaristeve]

Originally Posted by johnny_vitz

NGK makes a quality plug for a good price. The only thing wrong with denso's most of the time (especially iridiums) is the price. The quality is there, they just want too much for them.

I can see how they're cheaper. Is that the only reason they're "better"?

Back in the day, the joke was, "NGK stands for No Good Kind". But, again, I never really saw how one plug could be better than another (for making power). I can see how quality might be different but then one would say, "xxx plugs are made better than yyy plugs."

Don't get me wrong; I am not defending Densos. I usually just walk into the dealership and ask for the right plugs and AFAIK, Toyota dealers always sells Densos.

[johnny_vitz]

Originally Posted by Yaristeve

Don't get me wrong; I am not defending Densos. I usually just walk into the dealership and ask for the right plugs and AFAIK, Toyota dealers always sells Densos.

I ran OEM denso plugs from the dealer until I boosted. I would recommend NGK for almost any import. I do not believe you make more power switching plugs, the only gain switching from copper plugs to platinum or iridium is the service interval (how long you can leave them in). There is no proof NGK is better than denso, it's just an opinion.

[Bluevitz-rs]

hopefully you used some sort of anti-seize on the threads, or come next time you change them they might be "welded" to the head. The metal in the spark plugs tends to react with the aluminum in the head causing them to bond together.

[auxmike]

Originally Posted by Bluevitz-rs

hopefully you used some sort of anti-seize on the threads, or come next time you change them they might be "welded" to the head. The metal in the spark plugs tends to react with the aluminum in the head causing them to bond together.

I put a little Mobil 1 on the threads before installing. I'm sure there's still plenty of that cosmoline stuff stuck inside the hole threads.

[swidd]

The stock ones I replaced at 86,000 were "welded" pretty good, and had almost rust-like bond to the cylinder head. I also achieved much better acceleration and cold start with new plugs, and it seems it bumped my MPG a little too.

[Hershey]

Years ago , would set the plugs to 0.40 for TOYOTA engines .

[Lil Abner]

I'm pretty sure you don't gap Iridium plugs! It will damage the electrode and pad.

[auxmike]

Originally Posted by Lil Abner

I'm pretty sure you don't gap Iridium plugs! It will damage the electrode and pad.

Sparkplugs.com states .044 for most of these Yaris fitments. I did'nt have a guage that went that big, but a .040 slid through without dragging.
I too was'nt planning on gapping the pin tip like electrode!

["G"]

Uhm ok? So what's the point of your post????? You changed your plugs and? I'm just trying to wrap my brain around your point?

Fyi denso and ngk make very good iridium plugs. You can't go wrong with either.

[auxmike]

Originally Posted by "G"

Uhm ok? So what's the point of your post????? You changed your plugs and? I'm just trying to wrap my brain around your point?

Fyi denso and ngk make very good iridium plugs. You can't go wrong with either.

If you mean me (the OP), I like to share pics and the procedure with other members to benefit the community overall. The "point" is to perhaps help others with my crappy pics and brainless thoughts about the experience of doing the job.
Are you "happy" now, can your brain start wrapping yet???

["G"]

Yes, now I understand your point and post. Basically a newb trying to help out other newbs who are just learning how to change their own plugs.

Originally Posted by auxmike

If you mean me (the OP), I like to share pics and the procedure with other members to benefit the community overall. The "point" is to perhaps help others with my crappy pics and brainless thoughts about the experience of doing the job.
Are you "happy" now, can your brain start wrapping yet???

[johnny_vitz]

Originally Posted by Lil Abner

I'm pretty sure you don't gap Iridium plugs!

^^ x10 - Definitely don't gap iridium or platinum tip plugs

[auxmike]

I put them in as they came from the box.
I can't imagine dealer techs messing with a gapper with a lot full of cars to be serviced...

[RedRide]

Denso make a performance and long life iridium plugs.

The difference with the perfomance plug it that it has a grove in the side electrode that is supposed to concentrate the spark and give a slighly better prerformance during rapid acceleration.
This groove is eroded away after about 30k miles and although the plug is still very servicable, the benefits of the groove are no longer present but, they wiil stiil perform like a standard iridium plug. This is why they say to replace them after about 30k.

I used the Denson performance plugs (IK16) in my Celica and they do seem to run slighty better. It's nothing dramatic however as it only a spark plug.
If you are going to change them at about 30-40 k miles anyway, you might as well go for go for the performance plugs.

BTW, I agree that 100k is way to long to change the plugs and most mechanics recomend at least pulling them out at 50k to inspect them and to prevent at them from seizing at the threads
So, if you are giong to pull them anyway you might as will replace them.

[RedRide]

You can gap an iridium plug. The problem is the genter iridium electrode can be easily broken if your not careful.

From NGK:
"These plugs are made to the most popular gap sizes. In case it is necessary to re-gap these plugs, carefully open the ground electrode using a pair of needle-nose pliers or a wire style gap tool. Do not use a gap wheel type tool that will pry against the center electrode and could possibly break it off."

In other words, just be careful and don't put any pressure on the center electrode.

[johnny_vitz]

It is highly recommended not to by most manufacturers. I know you CAN, but it is more likely you'll damage it then set the proper gap. They almost all come with the exact gap your engine needs (vehicle specific applications). I've been told by our NGK rep not to gap them

[RedRide]

Originally Posted by johnny_vitz

It is highly recommended not to by most manufacturers. I know you CAN, but it is more likely you'll damage it then set the proper gap. They almost all come with the exact gap your engine needs (vehicle specific applications). I've been told by our NGK rep not to gap them

Yes, manufactures tell people not to gap them because they know there are many idiots out there who wont heed their advise about the center iridium electrode or may not even be aware of it.

In addition, the ground electrode is not iridium and will erode as quickly as most any other high quality plug. Remember the electrode wear on the performance plug?
Also, it is always prudent to check the gap on any new plug as there is always a possibility that one may not be set to specs.

You can't damage the plug unless you go in there like a bull in a china shop and ignore the warning about the center elrctrode. Remember the electrode is sturdy enought to withstand all the explosions for 100k miles.