NGK Spark Plug ILKAR7L11 long term usage

I used the NGKs for 25k with no visible difference in performance. OEM were replaced at 65k on NA engine. Out of curiosity I measured the resistance of the used OEM and set of new NGKs. Both sets are within the specs but there is some difference between the sets:

New NGK spark plugs resistance kOhm: 5.03, 5.09, 5.46, 5.58
65k OEM spark plugs resistance kOhm: 3.99, 4.17, 4.26, 4.43
Interesting resistance numbers between the two. Thanks for posting!
 
Just ordered the NGK ILKAR711 from Advanced auto parts for $46.60. Authorized dealer and they match Rockauto prices. Will be getting them installed by my mechanic soon and will let you know how they perform on my 2016 CX-5 sport.
 
Just ordered the NGK ILKAR711 from Advanced auto parts for $46.60. Authorized dealer and they match Rockauto prices. Will be getting them installed by my mechanic soon and will let you know how they perform on my 2016 CX-5 sport.
This’s may be a trivia question. I usually order parts from Advancd Auto online then do pickup at a store nearby because sometimes the 10% coupon code will jump out. But I don’t believe I can do “price match” through the online ordering?

Changing the spark plugs on CX-5 is a very easy DIY job with a proper 14mm spark plug deep socket. If you prefer to have your mechanic doing the job, it won’t hurt to mention the low 12~14 ft/lbf torque value and no usage of any anti-seize compound.

If you can post resistance value of new and old set of spark plugs like Dzo20 did that’d be great!
 
This’s may be a trivia question. I usually order parts from Advancd Auto online then do pickup at a store nearby because sometimes the 10% coupon code will jump out. But I don’t believe I can do “price match” through the online ordering?

Changing the spark plugs on CX-5 is a very easy DIY job with a proper 14mm spark plug deep socket. If you prefer to have your mechanic doing the job, it won’t hurt to mention the low 12~14 ft/lbf torque value and no usage of any anti-seize compound.

If you can post resistance value of new and old set of spark plugs like Dzo20 did that’d be great!
There is an option for contact or customer service on their web page. If you click on that option they give you the option to chat with an agent. They will match RockAuto once you speak to them. They gave me the option to do the free pickup at my local store to avoid shipping charges.

Thanks for the info about the torque and not using anti seize. I'll mention it to him.
 
New NGK spark plugs resistance kOhm: 5.03, 5.09, 5.46, 5.58
65k OEM spark plugs resistance kOhm: 3.99, 4.17, 4.26, 4.43
Very good to know, thanks. Would be interesting to see if that 1ohm drop is there with new OEM plugs, or just a result of aging. Anyone else tested this with new OEM plugs?
 
THE NGK PLUG IS THE MAZDA PLUG, SAME PLUG. And never never gap this type of plug, not supposed to bend or modify the electrode or ground strap in any way. The only thing you're supposed to do is check for proper gap and then install.

THE NGK PLUG IS THE MAZDA PLUG IT'S THE SAME PLUG

rockauto is a solid supplier
 

THE NGK PLUG IS THE MAZDA PLUG IT'S THE SAME PLUG
No, they aren’t the same plug, at least cosmetically. ;) The additional Mazda logo imprinted on the ceramics insulator isn’t cheap to do, although the huge price difference between the OEM and NGK plugs can’t be justified by that special imprint. IMO there’s something we don’t know (ion sensing capability?) and only Mazda knows.

For example, the price difference between Mazda OEM oil filters made by Denso and Denso oil filters for Mazda 2.5L’s isn’t much significant like OEM spark plugs and NGK equivalents.
 
There's nothing special about the branded Mazda plugs. The ECU uses them for per cylinder combustion diagnostics, but this is not a Mazda exclusive technique. There are SAE papers available on the internet for free describing how this system works. The "magic" is in the ECU, not the plugs.

The ECU monitors how the resistance is changing across the spark plug gap when it is not firing the plug. As the gas in the cylinder is drawn in, then compressed, burned, and begins to expand, the resistance across the plug gap changes in a predictable manner. If the resistance changes in a way that doesn't correlate with the typical profile, the ECU concludes there was a misfire or knock event. The absolute resistance value of the plug doesn't matter for this, it's how it is changing through the compression, ignition, and expansion events.

The plug resistance is important because a really low value can cause the ignition circuit to draw too much current and burn up the ignition coils.

If you want to overpay for plugs, that's up to you.
 
Been a mechanic for a long long time, boeing 737 avionics, bell helicopters, sophisticated Marine applications. I have never heard of Ion Sensing Spark Plugs. Maybe it's a thing, dunno. Still gunna stand by my statement. Same Plug. NGK is the OEM supplier to Mazda for their spark plugs.. Mazda doesn't make spark plugs. The NGKs off rockauto are so cheap......hell, I might even consider doing something crazy and changing them every 40,000 miles! (Naw, plugs will go 60k ez). :). But.... being an aircraft mechanic I'm never going to fault anybody for buying OEM parts that's for sure
 
The spark plugs used on SkyActive-G need to be ion-sensing compatible with the built-in ion sensor in the coil pack and the resistance of the plugs needs to be 3.0 ~ 7.5 KΩ.

4FDEE44E-4D9A-4BC8-90A5-6B00A781EB25.png


783BC436-B979-421C-A649-CF6467EAA7D5.jpeg


And:

Anyone care to comment on this?

"Not knowing the specs of a USA CX5 I'm not 100% certain this will apply. ( I work in the New Zealand & Australian market )

The factory ignition system has a "Ion" sensor setup. Its basically a pre O2 sensor check of combustion using the ignition coil & sparkplug. I can't remember the exact details but I remember being taught we must use genuine sparkplugs and not aftermarket plugs.

Another of my 2 cents to consider before replacing sparkplugs in any Skyactiv Mazda."

http://www.aces.edu/~parmega/efi/temp/DIY-Ion-Sensing.pdf

"1.3.1 Simple..
A method to get to know whether ignition is too early or too late, on a cycle-to-cycle
basis. No extra intrusive sensors, no engine modifications. 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 ;), independent of the engine layout
and fuel."


There have been several people who had replaced plugs that did not have the proper ion feedback and it created a lot of trouble codes so you can watch out for that. I remember a 2013 that replaced a lot of parts before he purchased oem plugs and the codes went away. I suggest you search for engine codes on this site and read other experiences...


Also the ECU uses the spark plugs as ion sensors that are fucntion as in chamber knock sensors. This is why I would never run anything but an OEM plug if you want to maintain max rated power output and fuel economy for each fuel/air charge.. if the voltage is outside of a certain range (not sure what it is for the turboh, but it's in my WSM), then the ecu can't use the plug as a sensor as intended. Unless you tested a non oem plug with a Volt meter you won't know.


Until I know that non oem plug meets the workshop manual resistance of 3.0*7.5 kilohms) I wouldn't use a non OEM plug. The ecu uses the spark plug as primary knock sensor. If the resistance is out of spec then you could end up losing power and or mpg. I've been meaning to buy a cheap plug from Vatozone and test the resistance.


I bought a set of Ruthenium plugs for my NC1 based on the durability claims, but haven't installed them, yet. Still waiting on other parts.

Mazda would not be the first and might be the last to use spark plugs as a combustion chamber sensor. Since coil on plug systems came into use that has been possible. Why else would the coil have 4 connectors when it need a 2 to fire? For that reason, I'd be a little slow to change types.

Since Digs' OEM plug electrodes are rounded, it is not surprising new plugs felt better. They should be sparking more reliably/consistently.


And from OVT (OrangeVirus Tuning):

Without getting into too much detail...you guys really...really..really want to use OEM plugs....
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.
 
That is actually fascinating. So with the cop system, its setup to use the spark plug as a knock sensor for EACH cylinder. Pretty cool. So yea, I see what your saying that you do not want to stray from the correct plug or its not going to work as designed. We deal with this in the aviation world all the time. Its illegal to use the incorrect part. We call it "conformity to type". So, for example, you cant shorten a cable, use a different screw, use an incorrect spark plug, because thats not how the machine was when it got its Airworthiness Certificate from the FAA. But since this NGK is actually the exact same spark plug mazda sell at the parts counter I think everything is going to be ok. Its not a Champion spark plug with mearly the same heat range, threads, similar resistance, its not that. Its actually the same exact plug made by my favorite oem spark plug manufacturer...NGK. I think it will be fine. The only reason I would be willing to pay triple for the exact same spark plug would be for piece of mind when it comes to counterfeits. There are a lot of counterfeit NGKs out there. But gunna get mine from RockAuto when it's time. And I'll report back
 
The color coding on that wiring diagram didn't make a lot of sense to me on some of the coils. I almost thought it was cylinder deactivation enabled. But I see that's a 2.0 L. Interesting to see the 2.5 l wiring diagram turbo and NA WDs
 
The color coding on that wiring diagram didn't make a lot of sense to me on some of the coils. I almost thought it was cylinder deactivation enabled. But I see that's a 2.0 L. Interesting to see the 2.5 l wiring diagram turbo and NA WDs

The coils are connected to +12V (grey, connects to "A" on each coil) and ground (black, "D") on two of the wires. The third wire is the trigger from the ECU (various colors, "B" I think) that tells the coil when to fire. The fourth wire is the sensing wire ("C", I think).

Someone first thought of using the spark plugs to monitor combustion in the 1950's, but it wasn't practical without electronic ignition and digital computers. A number of manufacturers have used this technique since then (SAAB, BMW, and others). I think it hasn't seen wider use because the other methods of detecting knock (a piezoelectric sensor to detect the noise and/or accelerometer on the crankshaft) were "good enough".
 

Its not a Champion spark plug with mearly the same heat range, threads, similar resistance, its not that. Its actually the same exact plug made by my favorite oem spark plug manufacturer...NGK. I think it will be fine.
Even though the Mazda OEM spark plugs are made by NGK and Denso with additional Mazda imprint, but the price difference between the two makes me wonder there’s something we don’t know which makes the price on OEM plugs much higher. As I mentioned before such as the OEM oil filters, the price on OEM parts usually will be higher than the compatible parts made by the same manufacture, but can’t be 3 times as much higher.


The only reason I would be willing to pay triple for the exact same spark plug would be for piece of mind when it comes to counterfeits. There are a lot of counterfeit NGKs out there. But gunna get mine from RockAuto when it's time. And I'll report back
This would be a part of reasons I’d pay more getting the OEM plugs to avoid counterfeit NGKs. I firmly believe there’s no free lunch; and if it’s too good to be true, it probably is.

Speaking about RockAuto:

You nailed it!

The car came to me after new plugs were put in by another mechanic.

I got another CX-5 to start testing/swapping parts. Started with coils, then plugs, and noticed a big difference in the plug type in the working CX-5.

Plugs are $32 a piece at the dealer!

Be careful, RockAuto lists those Bosch Double Iridiums as compatible. THEY ARE NOT!

Thanks for all the help! Hopefully this post helps someone else.
 
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That is actually fascinating. So with the cop system, its setup to use the spark plug as a knock sensor for EACH cylinder. Pretty cool. So yea, I see what your saying that you do not want to stray from the correct plug or its not going to work as designed. We deal with this in the aviation world all the time. Its illegal to use the incorrect part. We call it "conformity to type". So, for example, you cant shorten a cable, use a different screw, use an incorrect spark plug, because thats not how the machine was when it got its Airworthiness Certificate from the FAA. But since this NGK is actually the exact same spark plug mazda sell at the parts counter I think everything is going to be ok. Its not a Champion spark plug with mearly the same heat range, threads, similar resistance, its not that. Its actually the same exact plug made by my favorite oem spark plug manufacturer...NGK. I think it will be fine. The only reason I would be willing to pay triple for the exact same spark plug would be for piece of mind when it comes to counterfeits. There are a lot of counterfeit NGKs out there. But gunna get mine from RockAuto when it's time. And I'll report back
I just got the NGK plugs from Advanced Auto Online. They are are an authorized distributor per NGK. Advanced will price match Rockauto if you chat with them online, and will let you pick it up at their local store or even ship it to you if you prefer.
 
Even though the Mazda OEM spark plugs are made by NGK and Denso with additional Mazda imprint, but the price difference between the two makes me wonder there’s something we don’t know which makes the price on OEM plugs much higher. As I mentioned before such as the OEM oil filters, the price on OEM parts usually will be higher than the compatible parts made by the same manufacture, but can’t be 3 times as much higher.



This would be a part of reasons I’d pay more getting the OEM plugs to avoid counterfeit NGKs. I firmly believe there’s no free lunch; and if it’s too good to be true, it probably is.

Speaking about RockAuto:
Serves them right. Who the heck would use Bosch spark plugs anyway. Especially in a Japanese engine when you can find oem ngks. Sounds like they didn't know what they were doing. Back in the day it was a reputable brand. Now they are at the Dorman/Fram level
 
I just got the NGK plugs from Advanced Auto Online. They are are an authorized distributor per NGK. Advanced will price match Rockauto if you chat with them online, and will let you pick it up at their local store or even ship it to you if youR prefer.
That's cool I didn't know that. O'Reilly will also price match Amazon. I did that multiple times in the last few years. NAPA won't, tried, said its a company policy not to price match. Really ..... click
 
So nobody has tried Mazda OEM “Vaule” spark plugs for the 2.5L NA? :unsure:

View attachment 317783

Mazda Value Line Skyactiv Spark Plugs (set of 4) PE5R-18-110-MV

I’ll check them out when I have a chance to be at my Mazda dealer.
Thats just sad. When the parts guy at the Mazda dealership handed me the Mazda VALUE oil filters I told him ha can put those right back on the shelf! Haha. No value parts going on my car, just genuine NGKs off rockauto! Haha, couldn't resist to get that in.
 
Watch out for this brand. I purchased a generator and had these in there but in the manual it gave you the NGK part number as the alternative spark plug. These went right into the garbage can
 

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