Spark plug burn marks, normal? 2019 CX-5 GTR

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19 CX-5 GTR White on White
Just changed the plugs, 35k miles. Are the burn marks normal? All 4 plugs were the same.

Looked closely under a magnifier, didn’t see any cracks, just the discoloration.

It’s been a while since I have changed any plugs, however I don’t recall seeing this before.

Thanks.

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OOPS, sorry. Didn't notice it was a turbo and didn't know that a 40K change was advised for that engine. It's getting to be a full time job keeping up with changes in this technological world. Can't wait to see the learning curve once EV goes mainstream. Of course maybe by then some of us won't really care.
 
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yep. back in 2007 when first iridiums started showing on the market they gave them 60k miles usage (denso). But on my turbo 4cyl they didnt last more than 40k and on a high-rev 8000rpm 4cyl non turbo they were toast around 50k and that was on non direct injection with lower compression ratios than todays Mazda engines. Something I noticed back then was that the fuel grade also played a role. The higher the fuel grade the better. But they also didnt have the eco bio crap additives that they add nowadays to all fuels.
 
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Just changed the plugs, 35k miles. Are the burn marks normal? All 4 plugs were the same.

looked closely under a magnifier, didn’t see any cracks, just the discoloration.

It’s been a while since I have changed any plugs, however I don’t recall seeing this before.

thanks.

View attachment 300388
What kind of spark plugs you’re using now? Mazda OEM、NGK、or something else?
 
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⋯ Can't wait to see the learning curve once EV goes mainstream. Of course maybe by then some of us won't really care.
Actually for an EV there aren’t much we need to do on maintenance and repair, hence nothing to learn. And not much we can do for any repair unless you have custom-made computers to hook up the EV diagnosing any problems.

We’re still able to work on the Hybrid and PHEV though.
 
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Corona stain???

The only part that matters is the gap and the nose of the insulator that's inside the combustion chamber. You didn't show that.
 
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Mazda OEM.

$24 Each. Expected them to be gold plated at that price.
I did that too and they showed up as Mazda branded NGK plugs with the same NGK part number that the NGK's would have been. I will not be buying the OEM ones in the future.

Anyway all mine looked that way too when I changed them, its normal.
 
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I did that too and they showed up as Mazda branded NGK plugs with the same NGK part number that the NGK's would have been. I will not be buying the OEM ones in the future.
The additional “Mazda” imprint to the insulator of the spark plug costs some extra money, but to double the price by Mazda which doesn’t make sense if all the markups are only from the imprint. Something else must be added to Mazda genuine spark plug to have such huge markups.
 
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The additional “Mazda” imprint to the insulator of the spark plug costs some extra money, but to double the price by Mazda which doesn’t make sense if all the markups are only from the imprint. Something else must be added to Mazda genuine spark plug to have such huge markups.
That's been the theory, but no one can confirm.
 
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The additional “Mazda” imprint to the insulator of the spark plug costs some extra money, but to double the price by Mazda which doesn’t make sense if all the markups are only from the imprint. Something else must be added to Mazda genuine spark plug to have such huge markups.
Cost to produce, and price are very different. Mazda needs their profit, plus they need to be inventoried, distributed, shipped distinctly and have a much smaller adressable market - since nobody but Mazda owners will buy them.
 
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Cost to produce, and price are very different. Mazda needs their profit, plus they need to be inventoried, distributed, shipped distinctly and have a much smaller adressable market - since nobody but Mazda owners will buy them.

It's perfectly plausible that there is something different about them other than the branding, but I wouldn't assume that from the price.
Personally I would be inclined to believe if they were actually different in any way besides the branding, they would have changed the model number on it. Mine had the NGK model number on it.

At least that's what I would believe, but who knows.
 
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