Spark plug replacement surprise

both the plug for my 2.p0op and 2.5 have a plug with two points on them. That NGK does not have a lower point.

Exactly. So far I've only seen one photo of a plug I would run in my CX-5. That's the one that says Mazda. Aren't there any compatible aftermarket plugs with opposing electrodes?
 
It's really a moot point. I'm sure that denso, ngk, others make an aftermarket equivalent that works just as well as oem. I suspect that one of those manufacturers even make the plugs for Mazda. I don't Mazda has their own spark plug plant!

Yeah I think its a generic stock photo. I'm just glad these are long life plugs. I don't plan on changing them until after 75k miles. I'll probably go stock OEM. Hopefully they'll be cheaper in about 3 years from now.
 
Exactly. So far I've only seen one photo of a plug I would run in my CX-5. That's the one that says Mazda. Aren't there any compatible aftermarket plugs with opposing electrodes?

It looks like the Denso Iridium TT (twin tip) fits the bill, IXEH20TT for both engines.

$_3.jpg


Available for less than $8 each.
 
Yes!!! Good find Mike M.

There's a reason for the "TT" at the end of the part number which means twin tip. Check out their website. http://densott.com/ with detailed explanation. This part is interesting (along with the cool pics) "With this unique design, there are literally two “tips”: a 0.4-millimeter Iridium center electrode, and a 0.7-millimeter Platinum ground electrode. DENSO’s patented Twin-Tip technology was first used on original equipment spark plugs for luxury and performance cars. Now, that technology is available to everyone."
 
That's the one alright

It looks like the Denso Iridium TT (twin tip) fits the bill, IXEH20TT for both engines.

$_3.jpg


Available for less than $8 each.


Yep another source confirms: According to the application checker at Amazon/Denso, that plug fits our 2.5L Cx-5. Hell, even Amazon sells them for $7.99 each!

Dealer markups are rich, but this is outrageous!
 
It looks like the Denso Iridium TT (twin tip) fits the bill, IXEH20TT for both engines.

Available for less than $8 each.

Excellent find. This will be very useful in the future.
 
MikeM. Is this the spark plug recommended by DENSO for the Mazda SkyActiv engine? The DENSO plug list the ground electrode as Platinum and the OEM is Iridium for both ground & center, so there appears to be a difference in materials.
 
MikeM. Is this the spark plug recommended by DENSO for the Mazda SkyActiv engine? The DENSO plug list the ground electrode as Platinum and the OEM is Iridium for both ground & center, so there appears to be a difference in materials.

Yes, Denso recommends it for both 2.0L and 2.5L CX-5.

The engine will never know what the electrode is plated with. Denso claims 100,000 miles+ and says their iridium tips have the highest concentration of iridium vs. any plug on the market.
 
Without getting into too much detail...you guys really...really..really want to use OEM plugs....
 
Without getting into too much detail...you guys really...really..really want to use OEM plugs....

"Why?" is a good question. And please don't tell us it's proprietary information...
 
Without getting into too much detail...you guys really...really..really want to use OEM plugs....

First the moly, then filters, plugs...

Next I will be told that I must get my fuel from the dealer's SkyActiv pump exclusively!
 
First the moly, then filters, plugs...

Next I will be told that I must get my fuel from the dealer's SkyActiv pump exclusively!

I consider each separately. In the case of the air filter, it would be difficult to make the case there is one better than the OEM filter (and it's very reasonably priced). At least I've never seen a convincing argument there is something better available.
In the case of the motor oil, the Mazda oil tests very well in independent tests, and is not too expensive. Perhaps someone could make the case that you could save a couple bucks and have similar performance. But I like the idea of molybdenum coating the wear surfaces and no one has made a good case that another oil would be better.
In the case of the oil filter, the Mazda OEM filter has been cut open and the inspection determined it has quality construction. It's also very inexpensive. Some aftermarket filters cross reference to vehicles that Mazda recommends a different filter for. That troubles me as bypass pressures can be different. This is a no-brainer because the OEM filter is so inexpensive and you know it has the approved bypass pressure,

Now with spark plugs we have an entirely different situation (at least with regard to information that has been posted on this CX-5 forum). Primarily the fact that OEM plugs retail for about $100/set while the Denso plugs retail for $32/set. If I can replace my plugs with the functional equivalent for $70 less, guess what I'm going to do?

Now the gentleman from OVT has alluded that they are not the equivalent by saying "Without getting into too much detail..." Yet he provided NO detail as to why the Denso plugs are not the functional equivalent. Usually, car enthusiasts want to share their knowledge, not get into cat and mouse guessing games. I'm not saying the Denso plugs are the functional equivalent because I really don't know, they could have different resistance values, etc. But without specific evidence to the contrary, I'm going to spend $70 less. Then, if my MPG declines, I get radio interference or lose power/torque, it's a simple matter to switch back and I'm only out $32. But before my plugs are due for replacement, I expect there will be other data points provided by other owners (or perhaps OVT himself) that will fill in the blanks.

But no one on this forum has ever forced anyone to their belief, people have just stated their opinions and (sometimes) supported those opinions with facts or logical reasons supporting their opinions.
 
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the reason is because the ECU uses the ignition coils, which measure a resistance across the OEM plug for pre-ignition, and extremely low levels of knock retard the knock sensor cannot pick up, along with that it gives the ECU individual cylinder information, the spark plugs are actually used "as a sensor."


How it works exactly is proprietary information that I am not willing to share, you want to use OEM plugs.
 
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the reason is because the ECU uses the ignition coils, which measure a resistance across the OEM plug for pre-ignition, and extremely low levels of knock retard the knock sensor cannot pick up, along with that it gives the ECU individual cylinder information, the spark plugs are actually used "as a sensor."


How it works exactly is proprietary information that I am not willing to share, you want to use OEM plugs.

If I understand you correctly, as long as the resistance value of a replacement plug is the same as the OEM plug then this will not be an issue?
 
Just because something works doesn't always mean it is the best option. We do know that the OEM plug uses different electrode material, as I stated earlier. Ed
 
OVT made an interesting reference to How the spark plug is part of a system to elevate pre-ignition and control knocking. I have read something similar but, would like to see the link, explaining more detail. I have no doubt that the DENSO plug is a good substitution but, at his point in time, I would go with the OEM plug. Ed
 
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