Unnecessary spark plug replacement?

Ordered Mazda plugs which just arrived.

How many times per vehicle life do you change the plugs? 1-2 times 99% of the time. I figured it ain't a place to save 50 bucks.
 
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Ordered Mazda plugs which just arrived.

How many times per vehicle life do you change the plugs? 1-2 times 99% of the time. I figured it ain't a place to save 70 bucks.
Curious if they will look the same as the ones I got when you get them.
 
They might look the same.

I've read here that apparently Mazda's plugs can provide resistance(?) readings while ngk do not. (or something of this nature?)
 
⋯ I've read here that apparently Mazda's plugs can provide resistance(?) readings while ngk do not. (or something of this nature?)
That was a wrong guess. Based on post #47 from Anchorman, two recommended OEM spark plugs listed in our owner's manual both are resister type. PE5R-08-110 is NGK ILKAR7L11; PE5S-08-110 is DENSO ZC20HPR11. OEM plugs do have MAZDA mark and its part # printed on the ceramic insulator.
 
Toyota V6 trucks are known to have NGK and Denso plugs...at once in the same engine. Look it up:)

Denso Iridiums in the V8 of my GX. Service interval is 12 years or 120K (~193k km) miles in that vehicles owner's guide.

It's gonna be a number of years before I will be replacing plugs in my CX-5 but will go OEM when I do.
 
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That was a wrong guess. Based on post #47 from Anchorman, two recommended OEM spark plugs listed in our owner's manual both are resister type. PE5R-08-110 is NGK ILKAR7L11; PE5S-08-110 is DENSO ZC20HPR11. OEM plugs do have MAZDA mark and its part # printed on the ceramic insulator.

Purely for info, that is the Mazda parts website.
 
Purely for info, that is the Mazda parts website.

Mazda site also told me there was 3m tape in 4 specific locations under my spoiler and how to remove it. There was none. Mazda dealer even confirmed it was in their supply chain. Again, nada, when I removed the spoiler. Stuff is fickle.
 
IMG_1236(Edited).jpg

Just got a set of new plugs from the Mazda dealer. This is on the box. Same numbers (both) are printed on the insulator of each plug. Sure looks to me that NGK provides OEM plugs for Mazda.
Bill
 
So question...I didn't get around to doing the spark plugs over the weekend as my garage was hotter than hell and I was pretty done after doing the AT shifter switch.

So for replacing the spark plugs, do I need to disconnect the negative battery terminal first, and do I need to use that anti-seize gloop? I did not think I did, but thought I should double-check.
 
So question...I didn't get around to doing the spark plugs over the weekend as my garage was hotter than hell and I was pretty done after doing the AT shifter switch.

So for replacing the spark plugs, do I need to disconnect the negative battery terminal first, and do I need to use that anti-seize gloop? I did not think I did, but thought I should double-check.

Not sure that you really need to disconnect the battery, though I always do when I work on my car. Since I use a torque wrench to tighten the spark plugs, I don't use anti-seize lubricants since they affect the torque readings and I could end up over tightening the plugs.
 
Not sure that you really need to disconnect the battery, though I always do when I work on my car. Since I use a torque wrench to tighten the spark plugs, I don't use anti-seize lubricants since they affect the torque readings and I could end up over tightening the plugs.

Perfect. Thank you for this answer. I will be using a torque wrench as well, so will forego the anti-seize.

Do I have to do anything special when I reconnect the battery, or will everything be good to go?
 
I know my mechanic always uses the anti seize. You will have a bad time on the next swap if they do seize.
 
Spark plugs are so easy it's the only thing I've always done myself since my very first car. I've never used anti sieze.
 
Perfect. Thank you for this answer. I will be using a torque wrench as well, so will forego the anti-seize.

Do I have to do anything special when I reconnect the battery, or will everything be good to go?
Not that I know of. Once you're done, reconnect the battery and you are good to go.

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On my Speed3, I torque the spark plugs to around 12 ft-lb. I don't think that's tight enough to need anti-seize but I'm not a mechanic though.

Edit: I have not had to do spark plugs yet on our CX-5 because it only has 32K miles right now. Long way to go before I have to replace them.
 
I think this is one of those ounce of prevention things. I certainly wouldn’t say required but like I said my mechanic always does and I’m sure he does it for a reason. It’s a really bad time bad time if they seize and they are in there for quite a while with the relatively long interval Mazda uses.

He also suggested it to me for my centering rings that kept sticking to the hub when I took the wheels off. It helped. They still kinda stick but come off much easier.
 
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.

I'm not so sure about that...

PE5R = NGK ILKAR7L-11
PE5S = Denso ZC20HPR11

That's stated in the factory parts catalog
 
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