Unnecessary spark plug replacement?

Yes. The point I was trying to make is that we haven't heard of issues using NGK spark plugs. So I think NGK makes generally good spark plugs. I stay away from Denso spark plugs because there were one or two that cracked when they were trying to remove it.

Agree in general NGK is solid.

Those have no markings so I don’t care if Amazon says they’re NGK they’re probably knock offs.

And as was stated you want OEM because of the propriety design for their secondary sensor function.
 
I’m sure it’s possible after market exist that have the correct design for that secondary function. I’d want to verify that if it were my car though.
 
Ugh this is so confusing to an amateur who doesn't know jack about spark plugs like me. :(
 
And these don’t look like what the OP posted!

EDIT: Those must be generic pics because mine had tips.

Okay I'm confused. I can't remember if I used Denso's or NGKs on the CX-5.

Just go OEMs. They're cheap now :) That's what I'm gonna do with the Mazda6
 
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The give away for me in the OP picture is there is nothing printed on the insulator. No brand or part number. That screams knock off.

Every spark plug I’ve ever bought had that printed on the insulator.
 
Why there's no any model imprint on ceramic insulator of NGK plug?

Actually there is one, but on the other side of the insulator, I took a photo of it.

a.jpg

I also found an interesting pic on eBay, the seller claimed that it's the OEM spark plugs for CX-5.

s-l1600.jpg
 
That's weird as mine actually have something printed on the insulator, here is the pic:

a.jpg
 
Actually there is one, but on the other side of the insulator, I took a photo of it.

View attachment 219299

I also found an interesting pic on eBay, the seller claimed that it's the OEM spark plugs for CX-5.

s-l1600.jpg
People always use this as the evidence that Mazda PE5R-18-110 spark plug is the same as NGK ILKAR7L11 plug. But the imprint on ceramic insulator is different.
 
That's weird as mine actually have something printed on the insulator, here is the pic:

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With all the Mazda and NGK spark plug pictures available here I still wish there're more side-by-side comparison pictures beteeen Mazda PE5S-18-110 and NGK ILKAR7L11 spark plugs from different angles. I wish your side-by-side comparison picture has full plug view with NGK and model # imprint on ceramic insulator. And a close up at tip area side-by-side would be nice too. I'll find time checking the package of Mazda plug at my dealer and see if there's "ILKAR7L11" wording on it.

⋯ so I bought the new "OEM-like" spark plugs from Amazon (ILKAR7L11) and tools for installing them.

So I took a photo of it comparing to a new one.

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By the way, my OEM spark plugs are 'Mazda PE5S 18110"
UPDATE: Thank you all for replying me! I have all the new spark plugs installed anyway, and I will probably start a new thread to discuss about the performance of these new plugs. Here is a photo that shows what a spark plug looks like after one day of usage:

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PE5R-18-110 and PE5S-18-110 are basically the same spark plugs. "S" is standard spark plug but "R" is resister spark plug which adds a 5kΩ resistor in ceramic insulator to suppress ignition noise generated during sparking.

thanks for clarification Yrwei, it doesn't seem like we can buy the "S" version anywhere online though... when I Google only the "R" resistor version shows up....

PE5R-18-110, do you have any links to buy the "S" version that came with the CX-5 from the factory ?
 
So what's the verdict? I feel so confused on if the NGK's are fine or if I should just go OEM?

I was hoping to do this Saturday along with an oil change.
 
I’d go OEM. It’s not like they’re that expensive and the labor is the more expensive part anyway so if you’re doing yourself shouldn’t break the bank.
 
I’d go OEM. It’s not like they’re that expensive and the labor is the more expensive part anyway so if you’re doing yourself shouldn’t break the bank.

Cool, will go that route then, thanks.
 
Considering the cost of the OEM plugs are much cheaper now....I'd go with them. Likely the last plugs you'd but for that car too.
 
Nah he says he’s putting at least 300k miles on it.

Yep, there will be more spark plug changes in it's life LOL.

I'm just saying if I could take a '98 Jeep Grand Cherokee to 300k miles, I'm thinking my CX-5 should be able to do at least that. ;)
 
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