Unnecessary spark plug replacement?

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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Below are original post:
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I have a 2015 CX5 which now has about 73000 miles on it. According to the user manual, I should have the spark plugs replaced when it comes to 75000 miles.
I'd like to do things early, so I bought the new "OEM-like" spark plugs from Amazon (ILKAR7L11) and tools for installing them.

To my suprise, the old spark plug seems to be just fine, much better than I anticipated. How could a spark plug that has 73000 miles on it be in such a good condition! Of course, I failed to find any obvious flaws, but it's probably because I can't tell the real problems. So I took a photo of it comparing to a new one.

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Do you think this replacement is totally unnecessary?

By the way, my OEM spark plugs are 'Mazda PE5S 18110"

the old plugs looked fine because they're iridium tipped with a platinum ground electrode... they are hard metals and wear rates with them are extremely slow, that's why mazda and everyone else using iridium plugs can recommend high replacement intervals
 
Agree with that. I have a hard time believing Mazda...tiny Mazda... Came up with brand new plug tech.



Buys a vehicle because he likes the engine and transmission developed in-house by Mazda...

...feels Mazda is incapable of spec'ing a unique spark-plug.
 
Also thinks Mazda Isn't stupid enough to think a proprietary spark plug is a good idea. If Mazda developed their own spark plugs you think they'd...o I dunno...mention it somewhere?
"We're so smart we completely redesigned the spark plug!" Of course they would.
 
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they have... it's called ROTARY ENGINE

"They" as in Wankel?!

I wouldn't have a rotary in a car,though. Planes and go karts,though,whoo wee boy! Go kart here with a Wankel,sounds amazing, and it's hard to beat on bigger tracks,unless you've gotta CRF450R that's hooked up...
 
Also thinks Mazda Isn't stupid enough to think a proprietary spark plug is a good idea. If Mazda developed their own spark plugs you think they'd...o I dunno...mention it somewhere?
"We're so smart we completely redesigned the spark plug!" Of course they would.

So which plug did Mazda say to use?
Or are you trying to justify using non-oem parts mentioned nowhere anywhere by mazda or the product manual or the dealers?
 
So which plug did Mazda say to use?
Or are you trying to justify using non-oem parts mentioned nowhere anywhere by mazda or the product manual or the dealers?
To be clear. These OEM spark plugs have their OEM model number, but also the NGK model number, which to me screams rebrand and markup.
 
To be clear. These OEM spark plugs have their OEM model number, but also the NGK model number, which to me screams rebrand and markup.

Maybe. No one seems able to confirm that the resistance is the same or not. An example not in the car world, I know, but...

A friend of mine is a DoD manufacturer. One company cuts his material. This company also cuts material for many many others, as well as their own products. His m4 upper receivers cost more. Same company. Same metal. The difference is the tolerance and spec. His uppers interface with the barrel via a thermal fit. Very very few other companies do this on this interface. So one may say "just buy the upper from XYZ, same as his, they make both..."
Well...sortof.


So do we know that the plug is 100% NGK/Denso factory spec, or did mazda have their plugs tweaked in some way?
Proof?
 
Yea, Unob, companies do that all the time. Mazda doesn't make its own oil. They just pay someone to put a Mazda logo on thier oil so they can charge more. Just like these plugs. I think the onus of proof is on those that claim there is something unique about these, not on those of us that claim these are normal plugs. Other then the fact they are $100 for 4. Why is the burden of proof on us flat sparkpluggers? Colorado provided some proof but nothing from the other side. hehehe
If I was Mazda and I did create some new type of Spark plug i would make it very easy for you to find this info. You really think they would just not even mention it publicly? Anywhere?
"Our new design spark plugs increase resistance on the uptick of the downslice giving 1 mpg improvement over other plugs and providing 2 hp and 1 ft lb! They last 2x as long as normal plugs! They don't need anti seize cuz they're awesome!"
SOMETHING! Some benefit they would advertise. They wouldn't quietly create their own spark plug and then... not even mention it. Why bother then?
 
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OK, well first of all that document.... is from 2002. Further:
"The technology
can be applied to any internal combustion engine that is ignited by a spark plug
(or has a similar pair of electrodes installed)"

A spark plug... not a specific spark plug.
"Or has a similar pair of electrodes..."
Also pretty generic...
 
I’m taking it this way. The parts list says either can be used so Mazda consider them to be equal.

If I was offered NGK or Denso I’d be quite happy and if it didn’t say so on the box i wouldn’t know anyway. I apply the same logic to a Mazda oil filter.
 
Yea, Unob, companies do that all the time. Mazda doesn't make its own oil. They just pay someone to put a Mazda logo on thier oil so they can charge more. Just like these plugs. I think the onus of proof is on those that claim there is something unique about these, not on those of us that claim these are normal plugs. Other then the fact they are $100 for 4. Why is the burden of proof on us flat sparkpluggers? Colorado provided some proof but nothing from the other side. hehehe
If I was Mazda and I did create some new type of Spark plug i would make it very easy for you to find this info. You really think they would just not even mention it publicly? Anywhere?
"Our new design spark plugs increase resistance on the uptick of the downslice giving 1 mpg improvement over other plugs and providing 2 hp and 1 ft lb! They last 2x as long as normal plugs! They don't need anti seize cuz they're awesome!"
SOMETHING! Some benefit they would advertise. They wouldn't quietly create their own spark plug and then... not even mention it. Why bother then?

+2
 
Yea, Unob, companies do that all the time. Mazda doesn't make its own oil. They just pay someone to put a Mazda logo on thier oil so they can charge more. Just like these plugs. I think the onus of proof is on those that claim there is something unique about these, not on those of us that claim these are normal plugs. Other then the fact they are $100 for 4. Why is the burden of proof on us flat sparkpluggers? Colorado provided some proof but nothing from the other side. hehehe
If I was Mazda and I did create some new type of Spark plug i would make it very easy for you to find this info. You really think they would just not even mention it publicly? Anywhere?
"Our new design spark plugs increase resistance on the uptick of the downslice giving 1 mpg improvement over other plugs and providing 2 hp and 1 ft lb! They last 2x as long as normal plugs! They don't need anti seize cuz they're awesome!"
SOMETHING! Some benefit they would advertise. They wouldn't quietly create their own spark plug and then... not even mention it. Why bother then?

Yep, I do believe the Mazda Moly Oil is made by Idemitsu if I recall correctly?

As for the spark plugs, don't see any reason to believe these aren't the NGK plugs at this point, and no evidence has been provided to the contrary, so...
 
Ion Sensing in the Sky G is real and can be a problem with the wrong plugs. I think both the above plugs will work OK but take a look at this thread for a guy who spent a lot of time and effort with spark plugs that caused engine codes:
:https://www.mazdas247.com/forum/showthread.php?123862437-CX-5-2-0L-P0304-P0171-Help-needed-please

There is a ion feedback system from the spark plugs, take a look at:
http://nema.club/2014wsm/service h...0g0004400.html and
http://www.mcx5.org/spark_plug_inspe...2_0_-1154.html
make sure your plugs support this, you may need to put in Mazda plugs to make sure this is not the problem... Here is some of the theory
http://bmwmotorcycletech.info/ioniza...-susbystem.pdf
 
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