Spark plug replacement surprise

robertmazda

Member
:
2013 CX-5 Touring
Today I planned to replace the spark plugs on my 2013. I'm at 60,000 miles. The severe service schedule says to replace them at 75,000 but I do most of my work early.
Not wanting to spend $25 or more per plug on the OEM ones, I went to Amazon and bought the Bosch Platinum that it said was a match for my car.
So I grab the 5/8" spark plug socket that I've used on various cars for about 30 years and head out to the car to remove the OEM plugs. No luck. The socket is down all the way but it just spins freely, not grabbing the plug. I spent a long time trying to figure that out. The web says that 5/8" is standard. The 5/8" socket fit perfectly on the replacement plugs I got. Finally I find a website that refers to using a 9/16" socket on the CX-5. I found a long one of those in my tool box and it did the trick. If you search for a 9/16" spark plug socket they typically refer to certain Ford Triton engines only. Go figure...

So my warning to you is:
1) You most likely will need to buy a new 9/16" spark plug socket because your 5/8" one is too big.
2) When you shop you may be told to buy the wrong size spark plug. You want a 12mm thread size, NOT a 14mm thread size. I shopped online at various national retail chains and got mixed results. Some selected a correctly sized plug (Champion and Denso are the only ones I could find) and some sites selected a too large plug. One site told presented me with both 12mm and 14mm options.

My OEM plugs are the Mazda PE0118110.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
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Plano, Texas, USA
I was wondering are the spark plugs between SA-G 2.0L and 2.5L the same? Anyway $26.70 for each OEM plug is outrageous! Are they made of pure gold?

Yeah we appreciated the info on odd size and high price of these spark plugs although I may still go for the OEM plugs when the time comes.
 

Kedis82ZE8

'12 GX 460,'07 G35x / '15 CX-5 AWD GT w/Tech Pkg
Contributor
Owners manual seems to indicate the same for both motors: PE5R-18-110 or PE5S-18-110

Manual indicates they are Iridium plugs.


http://www.mazdaparts.org/mazda-skyactiv-spark-plugs.html

genuine-mazda-skyactiv-spark-plugs-set-of-4-2.jpg
 
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MikeM.

Member
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2013 Mazda CX-5 Touring AWD 2.0L
Owners manual seems to indicate the same for both motors: PE5R-18-110 or PE5S-18-110

Manual indicates they are Iridium plugs.

Iridium was over $1000/oz two or three years ago. Now it's down to a bit above $500. Of course they only use a tiny amount in each plug.
 

RG_Flyer

Member
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2016 CX-5 Sport MT6
I confirmed that these are 9/16" hex: Denso 4711 IXEH20TT Iridium TT Spark Plug
RockAuto has them for $5.55 each (minus a $2.00 rebate thru 31-Mar-16) for an effective price of $3.55 each.

I would be surprised if Mazda's OEM supplier was not either Denso or NGK. Most Japanese auto and motorcycle assembler generally use one or the other.
 

erhayes

Contributor
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2021CX5 Reserve
Seems very strange that the dealer plug cost is $$25.xx per plug and Rock Auto sells for $5.55 and both state iridium.
 

RG_Flyer

Member
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2016 CX-5 Sport MT6
Seems very strange that the dealer plug cost is $$25.xx per plug and Rock Auto sells for $5.55 and both state iridium.

A recent article stated that auto manufacturers have lost repair & part replacement revenue due to recent strides in reliability. The article suggested that higher part mark-ups may be forthcoming as a result.
That said, my wife's Honda Odyssey recently required a battery replacement. The OEM Honda was the best price at $99
Not sure why Mazda is trying to get $25 per plug. I have purchased many thin-wire iridium’s for much less!
 
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2016 Mazda CX-5 GT AWD w/Tech & i-Activesense
Has anyone tried something other then the iridium plugs? I thought I remember reading somewhere that iridium plugs gave very long service life but not necessarily the best spark. I know my protege5 always did better with standard copper ngk plugs replaced every year or so for about $1.50 a plug.

Is the direct injection or high compression the reason for the iridium plugs? Would a platinum or copper plug work? Maybe even provide a stronger spark?
 

erhayes

Contributor
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2021CX5 Reserve
The piston crown in the SkyActiv engine has a center pocket that the fuel in inject into. The spark plug is located over that center pocket. I suspect that Mazda did thousands of testing hours to pick the very best setup and plug type. I might even suspect that the Mazda OEM plug is taylor made for this engine. I don't think I will be trying to substitutes another plug in hopes of saving any money. Ed
 

Chris_Top_Her

Banned
Moderator
Contributor
:
San Antonio, Texas
:
'15 CX-5 Miata AWD
I've heard from a very reputable source who spoke with a mazda (racing) engineer that you shouldn't use a non iridium spark plug on this motor.. So pretty much OEM or OEM spec..
 

brillo54

Resident Curmudgeon
Contributor
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NE Indiana
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'16 CX-5 GT FWD
I'm all for saving a few bucks but consider this: At a cost of $108.08 for a set of 4 from Med Center Mazda and a replacement interval of 75,000 miles that's a cost of $0.0014411 per mile. Is it really worth it to gamble on your cars performance? Just my 2 cents (or 13.88 miles of spark plug cost).
 

Kedis82ZE8

'12 GX 460,'07 G35x / '15 CX-5 AWD GT w/Tech Pkg
Contributor
I'm all for saving a few bucks but consider this: At a cost of $108.08 for a set of 4 from Med Center Mazda and a replacement interval of 75,000 miles that's a cost of $0.0014411 per mile. Is it really worth it to gamble on your cars performance? Just my 2 cents (or 13.88 miles of spark plug cost).

Yeah... I will most likely go OEM years out unless some thread pops up in the years ahead that shows no long term adverse affects from the more modestly priced versions.
 
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2016 Mazda CX-5 GT AWD w/Tech & i-Activesense
I've heard from a very reputable source who spoke with a mazda (racing) engineer that you shouldn't use a non iridium spark plug on this motor.. So pretty much OEM or OEM spec..

Ok I'm not going to argue with you or your source, I believe you. I just wonder if he gave a reason as to why? just like to know the science or engineering behind it.
 

Chris_Top_Her

Banned
Moderator
Contributor
:
San Antonio, Texas
:
'15 CX-5 Miata AWD
Ok I'm not going to argue with you or your source, I believe you. I just wonder if he gave a reason as to why? just like to know the science or engineering behind it.

I was not given the reason, but it came up when I mentioned replacing my plugs. Tbh I was asked not even to repeat it.
 
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13' CX-5 and 16' Mazda6 both Touring w/Tech/Bose
I found some compatible plugs and instructions here: http://www.paulstravelpictures.com/...gine-Spark-Plugs-Replacement-Guide/index.html Denso FC20HPR8 (Mazda OEM # PE02-18-110), NGK DILKAR7F8 (Mazda # PE01-18110), NGK (3811) ILTR5A-13G, Pulstar ef1i, and Autolite XP5364.

There appears to be a noticeable physical difference between OEM spec and after market spec compatible plugs.

OEM:
file.jpg


And the NGK 3811 going for $12:
41Vzib-WFDL._SL1000_.jpg
 
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2016 Mazda CX-5 GT AWD w/Tech & i-Activesense
8024129161gallery.jpg


I think your photo may be wrong. These are the ones that came up for me when I searched for ngk iridium plugs for the cx-5. They look much closer to oem
 
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MikeM.

Member
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2013 Mazda CX-5 Touring AWD 2.0L
8024129161gallery.jpg


I think your photo may be wrong. These are the ones that came up for me when I searched for ngk iridium plugs for the cx-5. They look much closer to oem

I'm having trouble seeing how you think these are close to the OEM plugs. Don't the OEM plugs have the arc suspended between two "pin style" electrodes? The NKG plugs do not have this feature.

I wouldn't hesitate to run compatible aftermarket plugs but ONLY if they were the functional equivalent. That would include having two "pin style" electrodes.
 
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13' CX-5 and 16' Mazda6 both Touring w/Tech/Bose
8024129161gallery.jpg


I think your photo may be wrong. These are the ones that came up for me when I searched for ngk iridium plugs for the cx-5. They look much closer to oem

We're both right. Apparently the NGK has an OEM replacement and 2 compatible aftermarket ones. The aftermarket I posted (smooth ceramic) and the one you posted (threaded ceramic) are interchangeable. Just not sure which is the newer version. Source: http://www.sparkplugauto.com/ngk/la...rk-plug.html?gclid=COiMk7C77ckCFYhffgod95gD3g

"IMPORTANT NOTES:
NGK will be replacing ILTR5A13G - 3811 with this updated part information: LTR5BI13 - 90083
Will have same compatibility"
 
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2016 Mazda CX-5 GT AWD w/Tech & i-Activesense
Well they may be replacing part numbers but I still think the photo you posted is just a stock photo and not one of the actual plug needed. Here is a picture that I found for the ngk iridium plugs according to their website. Part number ILKAR7L11 and reference number 94124.
722dc82s-960.jpg


It's really a moot point. I'm sure that denso, ngk, others make an aftermarket equivalent that works just as well as oem. I suspect that one of those manufacturers even make the plugs for Mazda. I don't Mazda has their own spark plug plant!
 

Chris_Top_Her

Banned
Moderator
Contributor
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San Antonio, Texas
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'15 CX-5 Miata AWD
both the plug for my 2.p0op and 2.5 have a plug with two points on them. That NGK does not have a lower point. As the plug wears that point gets smaller