Unnecessary spark plug replacement?

He's a very knowledgeable Mazda enthusiast who firmly believes in using only Genuine Mazda parts unless there is something on par or better. Plus there are a whole lot of China fake goods out there for sale.

To me that spark plug change interval is ludicrous and based on results and projections from a controlled environment which none of us drive in. I would never leave my plugs in any engine for that long. But to each their own.
 
He's a very knowledgeable Mazda enthusiast who firmly believes in using only Genuine Mazda parts unless there is something on par or better. Plus there are a whole lot of China fake goods out there for sale.

To me that spark plug change interval is ludicrous and based on results and projections from a controlled environment which none of us drive in. I would never leave my plugs in any engine for that long. But to each their own.

That may seem like an awful long time, but as a data point, my former Mazdaspeed3 (DIRECT INJECTION, and Turbo), received spark plugs only when the previous owner got a misfire code. This happened at 138k miles and again at 281k miles, so it is possible for the NGK Factory Iridium plugs to go far beyond Mazda's recommendation.
 
That may seem like an awful long time, but as a data point, my former Mazdaspeed3 (DIRECT INJECTION, and Turbo), received spark plugs only when the previous owner got a misfire code. This happened at 138k miles and again at 281k miles, so it is possible for the NGK Factory Iridium plugs to go far beyond Mazda's recommendation.
Yeah 75K-mile recommended spark plug change interval on CX-5 is not long comparing to others. Change interval on most vehicles nowadays is 100K+ miles, such as 2018 Toyota RAV4 has 120K-mile interval, and Nissan Rouge is 100K miles.
 
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
Yep you're right and I've made correction on this in post #64 before your post based on those pictures presented by many others. Pictures have shown that OEM PE5R-08-110 plug has NGK's "ILKAR7L11", and PE5S-08-110 plug has Nippon Denso's "ZC20HPR11" model number printed on the ceramic insulator.

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.
 
Yeah 75K-mile recommended spark plug change interval on CX-5 is not long comparing to others. Change interval on most vehicles nowadays is 100K+ miles, such as 2018 Toyota RAV4 has 120K-mile interval, and Nissan Rouge is 100K miles.

Being that the Skyactiv engine was new and not a whole lot of real-world field consumer data available, Mazda kept it conservative. Mine were new looking at 75k. I think it should really be closer to 100k imho.
 
OK, so I said previously that I did not notice any performance difference after changing the plugs. I'm now retracting that statement. Today I had a chance to test high speed acceleration that I did not test before. It was way better than it used to be for example, going from 60 to 80. A VERY noticeable difference, it really pulled strongly. Now before I get any negative comments about being a tepid driver, let me just say that my right foot and the floorboard of the CX-5 are no strangers; more like best friends that meet up every chance they get! I have a heavy foot and totally enjoy very spirited driving. There really is no performance difference off the line or at lower speeds when you get on it, but when I floored it today at 60-65 it flat took off unlike it used too. So, for the price of a couple of oil changes, I am very happy that I changed the plugs!
 
Alright. So at 88,XXX miles I changed the plugs this morning after work. I checked the gap on the old ones and it was identical to the new ones. I feel like I wasted 20 minutes of my life on this mess, but maybe upon driving it, my time spent will be vindicated. We'll see tonight.
 
Alright. So at 88,XXX miles I changed the plugs this morning after work. I checked the gap on the old ones and it was identical to the new ones. I feel like I wasted 20 minutes of my life on this mess, but maybe upon driving it, my time spent will be vindicated. We'll see tonight.

Don’t be grumpy ;-)

You’ll tear up that lane when you try it later!!!
 
Alright. So at 88,XXX miles I changed the plugs this morning after work. I checked the gap on the old ones and it was identical to the new ones. I feel like I wasted 20 minutes of my life on this mess, but maybe upon driving it, my time spent will be vindicated. We'll see tonight.

Dont be grumpy ;-)

Youll tear up that lane when you try it later!!!
 
Alright. So at 88,XXX miles I changed the plugs this morning after work. I checked the gap on the old ones and it was identical to the new ones. I feel like I wasted 20 minutes of my life on this mess, but maybe upon driving it, my time spent will be vindicated. We'll see tonight.

Alright Mr. old man grumpy pants. ;)
 
Don’t be grumpy ;-)

You’ll tear up that lane when you try it later!!!

ROFL! I hope not. My well-meaning neighbor dropped some fresh garden veggies off on my porch earlier and he did his fair share of damage to it already because he didn't have AWD. I smiled and thanked him for the veggies, but tomorrow when I'm off, I'll be out there with my rake.
 
Kindof accurate. I'm jaded at about the level of most 60+ at 32. Probably because of all the s*** I deal with.

Yeah I sounded like you do right now about 3-4 years back during one job. Jaded so bad I still call it "PTSD" when I think about it somewhat jokingly, somewhat not jokingly. ;)

All I'll say is take care of your kidneys, folks. :)
 
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Alright. So at 88,XXX miles I changed the plugs this morning after work. I checked the gap on the old ones and it was identical to the new ones. I feel like I wasted 20 minutes of my life on this mess, but maybe upon driving it, my time spent will be vindicated. We'll see tonight.
So did you choose OEM or NGK?
 
Yeah I sounded like you do right now about 3-4 years back during one job. Jaded so bad I still call it "PTSD" when I think about it somewhat jokingly, somewhat not jokingly. ;)

All I'll say is take care of your kidneys, folks. :)

I dont know if I'd call it PTSD, but I dont look at people like others do.

Back to the spark plugs, no mpg change, and seat of the pants is inconclusive. Maybe? I dunno. If anything, throttle tip in is better. Idle quality may be a touch smoother. I dunno. Certainly not worth my 20 minutes.
 
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