Iridium Plug Question

[fostersafb]

I recently installed some Denso ITV22, one step colder plugs on the MS3. From what I have found they were supposed to be properly gapped already. Plus as far as I know gapping iridium plugs isnt the easiest thing to do without damaging them. Anyways, I wanted to check the gap, just to make sure. Carefully I slid the gapping tool between the center electrode and the ground electrode. As I did this I noticed a thin coating shed off of the underside of the ground electrode. After that I eyballed the rest of the plugs to check their gap as the one I measured was right on for the proper gap.

Did I ruin the plug? What was that coating I scraped off?

 

[bykeryder4life]

if you ruined the plug you will get a cel. put them in and drive it, then take them out and check what they look like. If all sounds and looks good and no cel from a misfire of something then you are golden.

 

[fostersafb]

if you ruined the plug you will get a cel. put them in and drive it, then take them out and check what they look like. If all sounds and looks good and no cel from a misfire of something then you are golden.

Ive been running them for a few hundred miles now and no CEL. There is just a slightly irradic idle that has made me a bit paranoid. I just cant remember if if was present before switching plugs.

So basically if somehting was wrong with the plugs it would be obvious?

 

[LBV]

I'd change out that one plug just for piece of mind. I used those plugs too and have never had anything flake off of them and I checked the gap on them all.

 

[fostersafb]

Thats exactly why I asked the question. Its been eating away at me. Every abnormal thing I feel now I keep thinking, its that spark plug, lol.

 

[bykeryder4life]

if the idle is getting funky then yeah change it out for peace of mind. if that doesnt help the idle maybe you have a vac leak...

 

[fostersafb]

if the idle is getting funky then yeah change it out for peace of mind. if that doesnt help the idle maybe you have a vac leak...

I wouldnt say its really irradic or anything just randomly irradic. It has been like that since the car was new. Also the car doesnt feel like its missing or anything wen driving.

Out of curiousity, would any of the sensors the accessport picks up show if a proper spark is being achieved?

 

[bykeryder4life]

ya i think AP can see spark advance. DH can I know

 

[turbo23]

what mods do you have that require a colder plug? I know alot of people are running them to prevent this and that, but they are not necessary unless you are running some sort of aftermarket turbo setup. You should not need colder plugs with just intake and exhaust setups. I actually believe they can be worse for your car. I only ran colder plugs in my rx7, but it was far from stock and making over twice its normal hp.

 

[leadf00t]

what mods do you have that require a colder plug? I know alot of people are running them to prevent this and that, but they are not necessary unless you are running some sort of aftermarket turbo setup. You should not need colder plugs with just intake and exhaust setups. I actually believe they can be worse for your car. I only ran colder plugs in my rx7, but it was far from stock and making over twice its normal hp.

I thought I read somewhere that they were recommended with the AP. Maybe I'm wrong.

 

[LBV]

Here's Cobb's wording:

"Our data has shown that the factory spark plug temperature range (6) and gap (~.034”) are
sufficient for stock boost levels and normal driving conditions. Although, operating the car with higher
than stock boost levels or with the calibrations that are on the AccessPORT, require that a spark plug
gap of .026” - .028” (6.6 – 7.1mm) be used on a 1-step colder temperature plug. Denso currently offers
this spark plug as part # ITV22 (please be sure to verify each plug is properly gapped before installing
them). Our experience has shown that operating your turbo-charged engine at higher than stock boost
levels requires that your spark plugs be replaced at around 15,000 mile intervals."

 

[turbo23]

I still feel that the plug would be alittle overkill. I know from personal experience, with an intake I was running over stock boost levels, and someone recommended to use colder plugs to prevent the stumble you can sometime gets when mashing on the gas in high gears. I ran them for about 3k and my car looked like a diesel when stepping in the gas, so much unburnt fuel it was terrible. I switched back over to my stock plugs, much cleaner, car didnt have the slower spool. Just from my experience

 

[fostersafb]

what mods do you have that require a colder plug? I know alot of people are running them to prevent this and that, but they are not necessary unless you are running some sort of aftermarket turbo setup. You should not need colder plugs with just intake and exhaust setups. I actually believe they can be worse for your car. I only ran colder plugs in my rx7, but it was far from stock and making over twice its normal hp.

From my subie days I remember the rule of thumb was every 100 hp go one step colder. However I have learned to trust Cobb's advice over the years.

Also from my DSM days, copper plugs were the only way to go.

In regards to unburnt fuel I can say that my tailpipe doesnt get nearly as sooty as it used to. Not sure if its the colder plugs or not but that says something.

 

[john blutarski]

I'd like to know how you're supposed to check the gap on these plugs without touching the fragile electrode. I have the same set waiting to go in.

 

[LBV]

I'd like to know how you're supposed to check the gap on these plugs without touching the fragile electrode. I have the same set waiting to go in.

You just have to be gentle with the feeler when you slide it through and obviously don't force it. If it doesn't go through, widen the gap a bit more and then re-try.

 

[john blutarski]

^^^ thanks

 

[leadf00t]

Here's Cobb's wording:

"Our data has shown that the factory spark plug temperature range (6) and gap (~.034) are
sufficient for stock boost levels and normal driving conditions. Although, operating the car with higher
than stock boost levels or with the calibrations that are on the AccessPORT, require that a spark plug
gap of .026 - .028 (6.6 7.1mm) be used on a 1-step colder temperature plug. Denso currently offers
this spark plug as part # ITV22 (please be sure to verify each plug is properly gapped before installing
them). Our experience has shown that operating your turbo-charged engine at higher than stock boost
levels requires that your spark plugs be replaced at around 15,000 mile intervals."

That was it, thanks.