Spark plugs suggestion

[walt101786]

i am doing some research...i have been told that NGK sparkpulgs are one of the top brands for yaris...but i am curious....which one do you guys perfer that could ensure i'll be getting a better improvement such as.....performance-by how much, fuel-by how much....and so forth...thank you

[sickpuppy1]

Get the heat range recommended by Toyota and get them in Iridium. Last forever it seems and better fuel/performance. Yes NGK is a very good brand. After a point, its personal preference really. I'm curious if the E3 plugs are all they're cracked up to be.

[YarisSedan]

Dont put anything in a Toyota besides NGK or Denso. Both are good.

[RedRide]

Originally Posted by YarisSedan

Dont put anything in a Toyota besides NGK or Denso. Both are good.

^+1

[Yaris Hilton]

As long as the plug sparks every time it's supposed to and doesn't overheat and cause preignition, what kind of plug it is will make no difference in performance or mileage. The stock iridium ones will serve you well till their recommended 100,000 mile change.

[RedRide]

The problem with leaving them in for 100k miles is they sometime seize up and are difficult to remove.
It would be wise to remove and inspect them after 50k mile or so.

Ther are also Denso "performance" iridium plugs that have an added groove in the side electrode.
Denso recomends that you change them after about 30k mile to retain their full benefit.
I used the performance plugs in my Celica and they do make a small improvemrnt in acceleration.
BTW, the Yaris and Celica GT used the exact same plugs.

Anyway, shure a plug can last 100k miles but, after a while, any plug can start to loose a bit of performace particularly under heavy acceleration.
The problem is, performance can drop off so gradually you wouldn't notice.

[sickpuppy1]

If it so gradual you don't notice, then its not much huh? lol I actually waited till around 100k on my civic and to be honest, I think most of the perceived improvement was mental..........no mileage change at all.
I have a mental need to do it, because I'm 55 and grew up around cars you had to change the plugs every 12-15 thousand miles.Along with the cap,rotor and points too,lol

[RedRide]

Originally Posted by sickpuppy1

If it so gradual you don't notice, then its not much huh? lol I actually waited till around 100k on my civic and to be honest, I think most of the perceived improvement was mental..........no mileage change at all.
I have a mental need to do it, because I'm 55 and grew up around cars you had to change the plugs every 12-15 thousand miles.Along with the cap,rotor and points too,lol

If that is what you believe, fine.

[Tamago]

since you're convinced that the "plugs slowly loose a bit of performance" you might as well explain exactly how they "loose" it? either a spark plug fires, or it doesn't. it's not rocket science.

[RedRide]

Originally Posted by Tamago

since you're convinced that the "plugs slowly loose a bit of performance" you might as well explain exactly how they "loose" it? either a spark plug fires, or it doesn't. it's not rocket science.

OK....So, plugs are good for the life of a an engine no matter how many miles that may be.?

It's a fact of life that all sparks are not created equal even with the same type of plug and the "qualty" of a spark will effect performamce to one extent or another.
Dyno tests bares this out.

You have some "learning" to do.

[ddongbap]

Originally Posted by RedRide

OK....So, plugs are good for the life of a an engine no matter how many miles that may be.?

You have some "learning" to do.

Tamago, this fool is calling you out.

Burn him like a Turbo Supra beats a Ferrari.

Btw, red, your logic can be done in reverse. If a spark 'looses' it, you should be changing it every trip.

[RedRide]

Hey guys, bury this horse.

[YarisSedan]

Every time the spark jumps the gap it slowly erodes the electrode eventually causing the gap to become wider. Copper plugs only last about 30k because of this before the gap gets too large its harder and harder for the spark to jump it. Eventually this may lead to premature ignition coil failure. More modern cars now switched to platinum and double platinum because it takes longer for it to erode. Now they have iridium which lasts even longer which is what we have in our cars. They are suppose to last 100k miles. After that they consider the electrode worn enough that it should be replaced.

If you want at 50k when you inspect them just put a small dab of antisieze on the threads that will insure they wont stick to the cylinder heads when you remove them at 100k to change them. Also make sure you dont try to remove them when the engine is hot. Let it sit for awile after its ran to cool down.

[Tamago]

Originally Posted by RedRide

OK....So, plugs are good for the life of a an engine no matter how many miles that may be.?

It's a fact of life that all sparks are not created equal even with the same type of plug and the "qualty" of a spark will effect performamce to one extent or another.
Dyno tests bares this out.

You have some "learning" to do.

so you're telling me that a spark has a quality? electricity jumps "slower" through the air the older the plug gets?

electricity (light as well) travels at 186,000 miles per second. the erosion of a plug, as already mentioned, does NOT affect the "quality" of the spark, it simply creates a further distance for the spark to travel. the farther the spark can travel, the more "bang" you get from each plug firing. in some cases this will yield a "better" burn of fuel. but again, this all goes back to the actual device that creates the high voltage electricity in the first place, the coils themselves. once the coil cannot create enough voltage to jump the eroded gap in the spark plug, the plug no longer fires consistently. but as the gap increases (up to the point of failure) the spark SIZE increases, meaning a plug actually gets MORE efficient at igniting fuel.. do you understand?

now, a fouled plug will have a shorter spark, simply because the electricity does not have to travel as far (due to carbon or other buildup) from the electrode. smaller spark (what you call quality) = less capability to ignite the fuel/air mixture inside the combustion chamber.

so, if iridium plugs are considered to be a 100,000mile plug, changing them at 50,000miles is pointless. have you ever actually pulled a denso IK22 out of your engine and looked at it? even a 100,000mile denso plug looks almost brand new, no visible signs of erosion (on a stock, non boosted engine).

quality of spark? c'mon dude.

[sickpuppy1]

Well, I believe RedRide is acccurate to an extent, plugs do go bad and they do get weaker over age. I wont dispute that. But I think it more due to quality of materials used and other factors such as fuel quality and driving style. My comment earlier about how we used to change points, plugs cap and such was true to because of the factors I just mentioned. Back when plugs were copper only they DID wear out since the copper was ate away by they constant sparking eating away at the metal. inefficient burning of fuel due to old school carburetors caused them to get carboned up quickly. I just think that with the increase in material quality of the plug, better control of fuel due to EFI and electronics and moderation of driving style (saving fuel) that Iridium plugs can go 100k with a very minimal lose of spark integrity. Which is not to say that there isnt some lose of spark quality over that time, but the amount is so small that a daily driver scenario wouldn't perceive the difference. If someone is doing rally driving or something, they would be more inclined to notice it I would think.

[Tamago]

someone please explain this so called spark quality....


a "worn out" plug will affect spark QUANTITY, but how can it affect quality? electricity jumps gaps, it doesn't have a quality, either it jumps or it doesn't jump (due to too-far of a gap, or fouling from carbon or other buildup).

spark quality (voltage) is determined by the coilpacks themselves, not the spark plug.

[auxmike]

Originally Posted by Tamago

have you ever actually pulled a denso IK22 out of your engine and looked at it? even a 100,000mile denso plug looks almost brand new, no visible signs of erosion (on a stock, non boosted engine).
quality of spark? c'mon dude.

Is that the part number and brand for the stock Yaris plugs then?

[RedRide]

Originally Posted by sickpuppy1

Well, I believe RedRide is acccurate to an extent, plugs do go bad and they do get weaker over age. I wont dispute that. But I think it more due to quality of materials used and other factors such as fuel quality and driving style. My comment earlier about how we used to change points, plugs cap and such was true to because of the factors I just mentioned. Back when plugs were copper only they DID wear out since the copper was ate away by they constant sparking eating away at the metal. inefficient burning of fuel due to old school carburetors caused them to get carboned up quickly. I just think that with the increase in material quality of the plug, better control of fuel due to EFI and electronics and moderation of driving style (saving fuel) that Iridium plugs can go 100k with a very minimal lose of spark integrity. Which is not to say that there isnt some lose of spark quality over that time, but the amount is so small that a daily driver scenario wouldn't perceive the difference. If someone is doing rally driving or something, they would be more inclined to notice it I would think.

Thank you.

As sickpuppy alluded to,........
It comes down to how performance oriented a driver is. Granted, the average driver who used it as grocery getter, etc would not notice any performance decrease.

However, like I said, there are reports of plugs seizing up in after leaving them in for 100k mille.
So, some on other forms are recomending removing and at least inspecting them after about 50k miles.

Also, why replace them after 100k mles? Is that some sort of magical number that sudenly makes a plug go bad or, do they deteriorate gradually over their life ?

I challange anyone to show me a dyno report that shows that performance is exactly the same with new plugs and with plugs with over about 75k miles on them.