Sparkplugs - odd gapping and heavy smell of gas?

[SilentJay]

So I just tossed in a new set of NGK Iridiums (on sale @ part source for $15 a set btw), and when I took out my old ones (89k) they smelled really strongly of gas.

Then I was taking the new ones out of the packaging and noticed that it says not to gap the new ones. I checked the gap on the old ones and used that gauge against the new ones, and the OEM ones are set much wider than the new ones! I've read that NGK supposedly gaps the plugs within OEM spec from the factory.

The car starts, and seems to be running ok, however I have 2 questions:


1) Is my car running rich? Any way I can determine/fix this myself?
2) Should the difference in gapping concern me?

[Default User]

I wonder if the ECU will remap the AF ratio now that you have newer plugs.

[SilentJay]

I was wondering that too. I did notice that my exhaust smelled less of gas, though there was a significant amount of smoke coming out despite it being around 3-4 degrees this morning.

[Thrizzl3]

$15/set huh J? i gotta pick up 2 sets then damn im way overdue on a tune-up

[Soyabean]

Hey Jason, what part number for the NGK sparkplugs did you get? Is the 06's the same as your 07-08? Mine is 2.3 also

[SilentJay]

So here are some interesting observations - my first drive on the new plugs:

* No slight hesitation or stutter when i'm in 5th gear and need to give it a little to overtake someone
* Butt dyno says it's got a bit more punch, but oddly enough, this could be substantiated by the fact that when i'm cruising at around 120, I'm normally at 3400ish rpm, whereas I now sit at just a hair over 3000


More importantly, I hope the gas consumption improves too!

[SilentJay]

Hey Jason, what part number for the NGK sparkplugs did you get? Is the 06's the same as your 07-08? Mine is 2.3 also

I picked up Iridium "NGK LTR5IX11", however i'm not entirely sure if my engine uses the same as yours - You need to talk to the guys at the counter anyway, since the plugs are kept in the back, so they can look it up for ya.

[bubba1983]

ull notice about 100km/per tank with new plugs....thats what i found when i switched the first time, albeit to bosch platinum's...haha

[SilentJay]

^^^ +100km/tank? That'd be awesome!!

I noticed the platinums, and the gimicky e3 plugs, but figured sticking to OEM stuff would work best.

[bubba1983]

jus going by my results...i went from jus over 500km/tank, to over 600km/tank after i changed plugs...your results may vary, but its atleast something to go by

[Soyabean]

wow. Seems like Im definitely due for a change

[Default User]

Any recommendations on a performance Coil?

[SilentJay]

I honnestly didn't think there was a performance option for coil-on-wire

[stock3]

So here are some interesting observations - my first drive on the new plugs:

* No slight hesitation or stutter when i'm in 5th gear and need to give it a little to overtake someone
* Butt dyno says it's got a bit more punch, but oddly enough, this could be substantiated by the fact that when i'm cruising at around 120, I'm normally at 3400ish rpm, whereas I now sit at just a hair over 3000


More importantly, I hope the gas consumption improves too!


The reason that the OEM plugs were wider is because the gap widens as the spark plug wears, so most likely the new NGK's were in speck, whereas the OEM's must've been severely out of spec since you were noticing decreased performance.

Regarding your high RPM when you cruise at 120. Is your car an automatic by any chance? If it is that would explain it, as your torque converter probably never locked for some reason, maybe because you had to press the accelerator further down to keep the speed up, but the computer thought you want to accelerate, so it would keep the TQ unlocked.

[SilentJay]

^^^ It must've been something really REALLY severe, as i've driven cars that have been beaten on (ex-rcmp cars), and have never had their gaps change drastically.

Unfortunately, I drive a 5spd.

[shu5892001]

wow. Seems like Im definitely due for a change

+1 Same here, already at 95K still on stock plugs. I bought a set of Denso Iridium for 56 shipped

[Skip]

how early should spark plugs be changed? I'm sitting at roughly 75k...I assume it wouldn't hurt?

[SilentJay]

I thought iridiums were good for at least 100k, but it wouldn't hurt to change earlier. I'm quite glad I did.

[shu5892001]

how early should spark plugs be changed? I'm sitting at roughly 75k...I assume it wouldn't hurt?

It's on the 120K service, but looks like everyone is changing early

[MajesticBlueNTO]

I picked up Iridium "NGK LTR5IX11", however i'm not entirely sure if my engine uses the same as yours - You need to talk to the guys at the counter anyway, since the plugs are kept in the back, so they can look it up for ya.

Going by the Iridium IX code, i'm guessing you're a 2006+ Mazda3 as that product code is for the longer reach plug.

Anyway, the stock plug gap is 0.052" (or 1.3mm) as shown here (http://sparkplugs.com/results_app.asp?productTypeID=1&AAIA=1432714). The OEM plug code is ILTR5A-13G where the 13 represents the gap size in mm times 10 (1.3mm)

The gap size on the plugs you got, LTR5IX-11, is 1.1mm or 0.043"

so, the gap on the OEM plugs did not increase significantly, the gap was bigger to begin with.

I don't have a 2006+ service manual but on the 2004, the gap range was:

1.25-1.35 mm {0.049-0.053 in}

I'm assuming it's the same as the OEM gapped plugs are 0.052"

what does this all mean? to stay within OEM-spec, the gap on the Iridium IX plugs with the 1.1mm gap should've been widened to 1.3mm. the package says not to gap it because a traditional feeler gauge gapping tool (http://img3.prosperent.com/images/250x250/content.westmarine.com/images/catalog/full/15674_f.jpg) will damage the iridium tip.

you're better off using a wire gauge gap tool (http://www.amazon.com/Motion-Pro-Gauge-Spark-Gapping/dp/B002NY0XWQ) with the attachment to widen the gap. just be careful when inserting the wire between the tip and ground electrode.


EDIT: didn't read the first post fully and missed the part where you said the old plugs smelled like gas. did you start the car and run the engine for a short period of time (i.e. not long enough to make it into Closed Loop mode) before replacing the plugs? if so, some excess fuel from running in Open Loop mode may have remained in the cylinder.

usually you run a smaller gap when you boost the engine so that you don't get spark blow out. however, running a gap that's only 0.2mm smaller (and 0.15mm out of OEM-spec range) shouldn't be that big of a deal.

[MajesticBlueNTO]

how early should spark plugs be changed? I'm sitting at roughly 75k...I assume it wouldn't hurt?

the OEM plugs have an Iridium tip and a platinum piece on the ground electrode. iridium is a better conductor than platinum (hence its use on the electrode tip) and platinum wears less than the material on the ground electrode (hence why a piece of platinum is bonded to the ground electrode). the OEM plugs were designed for longevity, which is why they're so much more expensive than plugs you can buy at Canadian Tire.

chances are that you won't need to replace the stock plugs for a long time....the best thing to do would be to pull them out of the head and inspect both the condition of the plug and the gap. if things are ok and you want to be cheap, apply some anti-seize to the threads and put them back in. this will prevent them from seizing to the head over time and being hard to remove when it does come time to replace them.

as for replacing them early, the question would be "what are you goals?" if you plan to push for more power, copper plugs are your best bet as they offer the best spark (copper being a better conductor than both iridium and platinum) but they will need to be replaced more often (20-30,000kms vs. 100-160,000kms).

replacing the OEM plugs with Denso Iridium or Iridium IX would be a cost saving measure and not for any type of performance (all other things being equal).

[jay jay]

Just to comment on the supposedly ground breaking E3's, well in short they are junk. I had them in my 2.3L mazda 3 and Fuel milege went way down and problems went way up. Defiantly not a good idea for mazda 3's.

[SilentJay]

Awesome answers, MajesticBlueNTO. My car is running well right now, but I may consider pulling 'em out and gapping them if I can get my hands on a newer-styled tool. I've actually got one that came with a 1982 Lada :chuckle

[n00bMeiSter]

So are the copper plugs better on performance but worse on fuel economy?
And the iridium ones are better on economy but not a significant improvement on performance?

[SilentJay]

Just an opinion, but I don't think you should look towards plugs alone for significant performance gains.

[cklwilliam]

can anyone tell me if i get the right one?
http://i138.photobucket.com/albums/q244/cklwilliam/DSC_0050-1.jpg
http://i138.photobucket.com/albums/q244/cklwilliam/DSC_0051.jpg

[cklwilliam]

anyone ? I just want to double check its the right iridum before i open it

[n00bMeiSter]

Just an opinion, but I don't think you should look towards plugs alone for significant performance gains.

Oh of course lol. I was just wanting to see if I correctly understood what was said.
I'm not expecting to put in a new set of plugs and suddenly get an extra 20whp+20lbft torque lol

[MajesticBlueNTO]

anyone ? I just want to double check its the right iridum before i open it

what year is your car?

these will work on a 2004-2005 but not on a 2006-2009 ....check the gap on the plug as i ran the TR55IX in my old 3 and it had a gap of 0.059" vs the recommended 0.052".

[n00bMeiSter]

what year is your car?

these will work on a 2004-2005 but not on a 2006-2009 ....check the gap on the plug as i ran the TR55IX in my old 3 and it had a gap of 0.059" vs the recommended 0.052".

Did that gap cause any problems?

[MajesticBlueNTO]

Did that gap cause any problems?

i gapped it down to 0.052" so i wouldn't know

[cklwilliam]

what year is your car?

these will work on a 2004-2005 but not on a 2006-2009 ....check the gap on the plug as i ran the TR55IX in my old 3 and it had a gap of 0.059" vs the recommended 0.052".


its a 2004 2.3 , so i guess its the right ones?

[shu5892001]

yes


its a 2004 2.3 , so i guess its the right ones?

[Default User]

anyone try those BOSCH Platinum 4's?
I'm gettting mixed reviews

[Harbour Rat]

I have not tried them in my Mazda3 but I put a set of Bosch Platinum+4s in in Mother's '01 Civic a few years ago. They worked fine, just as well as the OEM NGKs as far as I could tell.

The only spark plugs I recommend avoiding are Champions. In 25 years I've never got a bad spark plug from NGK, AC, Motorcraft, or Bosch but at least 1/3, probably 1/2 of the Champions I've bought were duds.

[McGuyver_3]

my moms murano has about 95k on it. The plugs are supposed to be good for about 120. When I pulled them they looked as if the engine was losing compression through the plugs. was very strange as i have never seen that before

[Harbour Rat]

The plugs look like there is something leaking between the ceramic insulator and the metal shell, near the hex? If so I have noticed that on a couple of sets of NGK plugs. I don't know if they really are leaking or if it is just some sort of sealant which squeezes out when the shell is crimped around the insulator during production.

[McGuyver_3]

The plugs look like there is something leaking between the ceramic insulator and the metal shell, near the hex? If so I have noticed that on a couple of sets of NGK plugs. I don't know if they really are leaking or if it is just some sort of sealant which squeezes out when the shell is crimped around the insulator during production.

Yes thats what happened. It looks like its been happening for a long time though. I deal with alot of bosch and NGK's at work and have never seen them like that before. we usually change them under service when the computer tells us to. Which is even stranger as i have replaced some with only 40k on them

[jcutner]

side note, i replaced my e3 spark plugs with ngk iridium's this weekend
hoping that the mileage will get back to where it used to be (closer to 600 a tank, compared to barely 500 with the e3's)

[cklwilliam]

anyone try those BOSCH Platinum 4's?
I'm gettting mixed reviews

that what the previous owner put in my car, and after i change to ngk iridum it's much smoother and more responsive

[Default User]

that what the previous owner put in my car, and after i change to ngk iridum it's much smoother and more responsive

Just what I needed to know. Thank you!!

I know they are decent (but pricey) but also depending on certain cars