spark plugs always tell a good story

[Saab9000]

Plug looks very good as far as deposits, but how was the gap? Substantially larger than spec? That could damage your ignition system depending on what system you have.

My Saab has a direct ignition cassette and if the gap is not kept near spec, the DI cassette life is substantially reduced. So even though I know the plugs will last 75k miles easily, I replace them about every 10k miles.

 

[TurboLuver]

Originally Posted By: zoomzoom


2001 Audi S4 2.7L V6...Engine design document states:

The pistons are forged to enable them to
withstand the high loads to which they are
subjected.





I would echo what Onmo'Eegusee posted, and add that "forged" is a process, not a material. I'm sure your pistons are of aluminum construction....

 

[zoomzoom]

Originally Posted By: Saab9000
Plug looks very good as far as deposits, but how was the gap? Substantially larger than spec? That could damage your ignition system depending on what system you have.

My Saab has a direct ignition cassette and if the gap is not kept near spec, the DI cassette life is substantially reduced. So even though I know the plugs will last 75k miles easily, I replace them about every 10k miles.


gap was fine(on the higher side of acceptable) these are double platinum so they didn't wear much.

each plug has its own coil..car was running great I upped the boost so I wanted to put a one range colder plug in there.

 

[crazyoildude]

with your sea foam showers and all the other additives its hard to tell. Honestly do you really think you need all those additives? The ones you mention are quality products i use sea foam myself at the shop but remember they clean very good but they do have some adverse effects and everything you put into your gas tank including the fuel works its way into your oil diluting it and changing the way the additives in the oil perform.. ever hear if it aint broke dont fix it.. i dont mean to sound like im talking down to anyone im not..Its just i've seen so many people love their engines to death putting all kinds of cleaners and who knows what in and then there is problems with fuel injectors and valves burning and so on..

 

[FZ1]

The oem platinum NGKs in my 02 v6 Accord had no rust on the threads and look (looking at them now) better with 90k than this plug. I don't use any additives and run Shell regular. I'll never go 6.5 years on plugs again. Two of the plugs were noticeably harder to turn. Motor does run more smoothly with the new NGK platinums. .02.

 

[FZ1]

P. S. Thanks for posting the picture. I was saving my old plugs to show to the Honda Dealer service guy to read on my next visit. Guess my old plugs wear was fine.

 

[Big Jim]

As far as I can remember the last use of cast iron pistons in production passenger car engines was the old "stovebolt" Chevrolet 6 cylinder. That engine ceased production in something like 1962, but they may have changed to aluminum pistons a few years before.

 

[ziggy]

So, what do dark balck carbon stains on the spark plug tip mean? i usually change mine every 2 years, and 7,000 miles in that time, and the tips, regardless of brand alwasy are burnt or covered in black stuf. I do use feul additives and conbusiton chamber cleanrers regularly, like every 3 months i add the gas additive stuff, aka seafoam, gumout, techron, ect
what do dark tips mean?

 

[FZ1]

Maybe you should not use the additives? I use the NGK platinum plugs because they were the oem spec but also because they last much longer. Fewer spark plug changes is fewer chances to strip a spark plug thread.

 

[ziggy]

Well, its not additives...not stuff i put in the oil, its cleaning agents used when i change my oil, every months..regain, techron ect, things like that.
I had read in a neons forum, its best to change your plugs every year, regardless, becuase time, weather, and combsution can take thier toll on a plug...yet, the average change is 2 years to 30,000 miles..
any truth to that?

 

[FZ1]

I think it depends on the type of plug used. Platinum plugs last much longer than standard plugs. The NGK platinums I used are pre gapped. I ran them 6.5 years and 90k before the first change.

 

[chevrofreak]

I have some NGK TR55GP's in my car. They made a massive improvement in how my car ran. I've pulled them several times to look at the tops of my pistons, and they pretty much all looked like the one in the pic, minus the rust. It had been burning a lot of oil, so that might be what caused the white coating.

 

[Big Jim]

Originally Posted By: FZ1
I think it depends on the type of plug used. Platinum plugs last much longer than standard plugs. The NGK platinums I used are pre gapped. I ran them 6.5 years and 90k before the first change.


There really is no such thing as a pre gapped spark plug. ALWAYS check and adjust the gap as needed before installing. NGK is no different from any other plug maker in this respect.

Even if they intend them to be pre gapped that may be for an application other than your car, and even if the application matches, production quality control just isn't that close.

 

[chevrofreak]

The NGK TR55GP's I put in were all perfectly gapped for me. I checked every one of the ones I put in and they were exactly the .054" needed.

 

[Big Jim]

At least you checked.

 

[parimento1]

In my Avalon, the plugs are NGK and have 90k miles on them, although they look brand new.

 

[Turbo_777]

Looks like they are burning well, I wouldn't worry about those little grey blobs. What would concern me is why the socket and washer are rusting...moisture in that area is likley to cause loss of current. I also noticed the sealing area on the washer, it doesn't look as wide as on the NGK's I use, but then I can't see it too well in the pic..check the torque settings on your plugs.
I found the Iridium/Platinum (Laser) plugs work well as replacements for the straigh Platinums...that is in a Turbo Opel and VW TFSI.

 

[zoomzoom]

Originally Posted By: ziggy
So, what do dark balck carbon stains on the spark plug tip mean? i usually change mine every 2 years, and 7,000 miles in that time, and the tips, regardless of brand alwasy are burnt or covered in black stuf. I do use feul additives and conbusiton chamber cleanrers regularly, like every 3 months i add the gas additive stuff, aka seafoam, gumout, techron, ect
what do dark tips mean?


I would say that you are running rich

 

[zoomzoom]

Originally Posted By: FZ1
The oem platinum NGKs in my 02 v6 Accord had no rust on the threads and look (looking at them now) better with 90k than this plug. I don't use any additives and run Shell regular. I'll never go 6.5 years on plugs again. Two of the plugs were noticeably harder to turn. Motor does run more smoothly with the new NGK platinums. .02.


Well this engine is 2.7L turbo V6 and produces 350HP, so 130HP per liter...that is a high stress enviroment so I was actually surprised by how well plugs looked like after 40K miles...

 

[zoomzoom]

Rust probably comes from me pressure washing engine couple times. I suspect some water got into plug holes...