2013~2016 Anyone install Ruthenium Spark Plugs yet?

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.
Good point! Why there’re 4 wires if the spark plug has no other functions such as ion sensing than just firing?
 
Lots of OEMs use 4 wire coils. In general, the 4 wires are:
1 - +12v
2 - ground
3 - trigger
4 - diagnostic

The only mystery there is the "diagnostic" wire, and different OEMs use it for different things. Some coils pulse that after successful firings to signal to the ECU that "all is well". What Mazda is doing with it I can't say, and unless someone hooks an oscilloscope to an injector while it's running we won't ever know.
 
Looks like the coils do have ION sensors.

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So after determining that the coil has ION sensing capabilities built inside, I guess my question would be, does it really matter if we use an aftermarket spark plug such as Ruthenium?
 
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If the resistance of the plug and the gap size is similar to the OEM, it's probably ok. Otherwise, the sensor behavior is not going to be what the ECU expects.
 
If the resistance of the plug and the gap size is similar to the OEM, it's probably ok. Otherwise, the sensor behavior is not going to be what the ECU expects.
I actually had some luck trying to measure the resistance of the Ruthenium's prior to installation. Shame that I used a crappy Harbor Freight multimeter and not something of better quality but I think it was somewhere between 3.1 - 3.3 kOhms. The issue was that the spark plug center electrode tip is so small because it has a double electrode design with both sides sticking inwards and I had trouble touching the center due to the clearance. As for the gap, both are gapped at 0.044" and I did confirm the gap with a wire gauge tool.

However, if someone else wants to take a shot at measuring the resistance, I would recommend one end of your multimeter leads to have an alligator clip or something that can clamp onto the terminal nut.
 
I actually had some luck trying to measure the resistance of the Ruthenium's prior to installation. Shame that I used a crappy Harbor Freight multimeter and not something of better quality but I think it was somewhere between 3.1 - 3.3 kOhms. The issue was that the spark plug center electrode tip is so small because it has a double electrode design with both sides sticking inwards and I had trouble touching the center due to the clearance. As for the gap, both are gapped at 0.044" and I did confirm the gap with a wire gauge tool.

However, if someone else wants to take a shot at measuring the resistance, I would recommend one end of your multimeter leads to have an alligator clip or something that can clamp onto the terminal nut.

Mazda CX-5 Spark Plug Inspection_03.jpg
 
The resistance is on the lower end of acceptable, but that may be because spark plug resistance tends to drift upward over time.

From what I can gather, the ignition coils are sensing ionization current and feeding that information back to the ECU. Depending on how advanced Mazda's implementation is, the ECU can determine if the combustion event occurs "as planned" vs. a misfire or a preignition/detonation based on the current flow across the plug gap and how it varies over time. This info can then be used to adjust timing on a per cylinder basis rather than on all cylinders in bulk.

Other OEMs have been using this technique since the 1980's, with varying levels of capability. If you want to experiment, be on the lookout for misfire check engine lights and a code reader might be a good idea to check for misfire counts (record this before and after swapping plugs).

I'd probably just stick with OEM spec plugs.
 
The resistance is on the lower end of acceptable, but that may be because spark plug resistance tends to drift upward over time.

From what I can gather, the ignition coils are sensing ionization current and feeding that information back to the ECU. Depending on how advanced Mazda's implementation is, the ECU can determine if the combustion event occurs "as planned" vs. a misfire or a preignition/detonation based on the current flow across the plug gap and how it varies over time. This info can then be used to adjust timing on a per cylinder basis rather than on all cylinders in bulk.

Other OEMs have been using this technique since the 1980's, with varying levels of capability. If you want to experiment, be on the lookout for misfire check engine lights and a code reader might be a good idea to check for misfire counts (record this before and after swapping plugs).

I'd probably just stick with OEM spec plugs.

Good points. I'll probably report back every 10-20k miles but I'm hoping nothing bad will happen. I changed to Ruthenium at 68,233 miles and I haven't really noticed much change in MPG. Start up wise, it feels better but that could also be attributed to being a new spark plug so I'm neutral in terms of that aspect. As of right now, no ill effects or misfires but YMMV. One thing I can say right now is that I wouldn't hesitate to use Rutheniums again if OEMs are too expensive or sold out though.
 
I hail from the days when spark plug changes were at 12,000 miles so whether the change interval for a new plug is 75,000 or 70.000 really makes me no never mind. If a new plug type can really provide a perceivable acceleration increase I'd be interested. But wouldn't it be necessary for the plug to somehow provide increased horsepower output to increase acceleration times? If the plug could do that I would think that would be banner news.
 
I installed the Ruthenium plugs on a 2015 with the 2.5L several weeks ago. I did so without hesitation, as I believe that NGK, as the maker of the factory Iridium's, wouldn't be likely to engineer a plug that didn't meet the needs of the car. Plus, they are actually now slightly less expensive as the Iridium.
 
I installed the Ruthenium plugs on a 2015 with the 2.5L several weeks ago. I did so without hesitation, as I believe that NGK, as the maker of the factory Iridium's, wouldn't be likely to engineer a plug that didn't meet the needs of the car. Plus, they are actually now slightly less expensive as the Iridium.
Would you say you noticed any perceivable differences between OEM and Ruthenium's?
 
1/25 Update:

My last plug change with the Ruthenium's was at 68,233 miles and now I'm at 71,000 miles (3k miles later). What I've noticed is that my MPG is pretty terrible at an average of 19.9/20 MPG and I seem to never even hit 280-300+ miles on one fill up anymore unless I tried really hard to drive the car till it's nearly empty. My Laser Iridiums (PE5R-18-110) arrived today and I'm planning to install them sometimes this week to see how big of a difference they make on the gas mileage.
 
1/25 Update:

My last plug change with the Ruthenium's was at 68,233 miles and now I'm at 71,000 miles (3k miles later). What I've noticed is that my MPG is pretty terrible at an average of 19.9/20 MPG and I seem to never even hit 280-300+ miles on one fill up anymore unless I tried really hard to drive the car till it's nearly empty. My Laser Iridiums (PE5R-18-110) arrived today and I'm planning to install them sometimes this week to see how big of a difference they make on the gas mileage.
PE5R-18-110? Do you mean you got Mazda OEM plugs or equivalent NGK plugs? Check the resistance on your new plugs and let us know before the installation.
 
It's the NGK equivalent from RockAuto. I'll try my best, I only have the crappy Harbor Freight multimeter and I'll most likely need alligator clips to even attempt this lol.

https://www.rockauto.com/en/moreinfo.php?pk=5922090&cc=3312788&jsn=1
No, you need only 2 probes coming with the multimeter. See the schematic in post #26 above.

PatrickGSR94 got his NGK 94124 plugs directly from NGK website for fear of counterfeit:

2014 CX5 Tune-Up items to replace?

Someone actually called NGK trying to verify if his NGK plugs bought online are genuine NGK plugs.
 
No, you need only 2 probes coming with the multimeter. See the schematic in post #26 above.

PatrickGSR94 got his NGK 94124 plugs directly from NGK website for fear of counterfeit:

2014 CX5 Tune-Up items to replace?

Someone actually called NGK trying to verify if his NGK plugs bought online are genuine NGK plugs.
I get that you need two probes but touching the base of the spark plug is easy, just touching the tip and getting it perfectly aligned isn't and it could be that I'm bad at doing it or because of the design of the multimeter tip. I did the same method using the Ruthenium one and I could barely get a reading out of it. Either way I'll redo it and see what happens, the alligator clips would definitely help holding the base portion in place while I can get a better focus on the tip of the plug. Might help if I have something to hold it in place but I don't.

I chose RockAuto for the plugs since it was cheaper than any Auto Parts store like NAPA/Advanced Auto Parts. I'll probably end up giving NGK a call too maybe but I suppose RockAuto wouldn't sell counterfeits (crossing my fingers).

Not sure about the quality of these alligator clips but it's only $2.99 + 20% off coupon so I can't complain. Would probably help others who are interested in measuring the resistance as well.

https://www.harborfreight.com/36-inch-low-voltage-test-leads-66712.html
 
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1/27 Update: Resistance Values for NGK 9124 (OEM: PE5R-18-110) (RockAuto)

@yrwei52 Here's the resistance values you requested for.
  1. (Optional) Multimeter: You can use this to measure the resistance of your old/new spark plug and according to Mazda, your PE5R-18-110 should be within 3.0 - 7.5 kOhms (kΩ). For my Ruthenium plugs, I was unable to get a reading at all and I've attempted multiple times (ground electrode and terminal nut were my contact points) but the only thing I can think of is that I am not performing this procedure correctly.
From Left to Right (In-Order)/kΩ:
  1. Spark 1: 0.428 - 0.429
  2. Spark 2: 0.404 - 0.405
  3. Spark 3: 0.418 - 0.421
  4. Spark 4: 0.545 - 0.549
Based on the measurements, all of my (4) spark plugs from RockAuto fall within the specifications that Mazda has listed. I will probably be measuring the Ruthenium's once I swap it out sometime this week or whenever I have a chance. The alligator clips seriously help and I can't recommend them enough. It's less than $3 with the 20% off coupon.

Questions/Observations:
  1. Should the resistance between all of these plugs be this much, especially Spark #4?
  2. Does it make a difference if I bought these plugs as a set of (4) vs individual spark plugs for the same type? For example, for desktop memory, it's recommended to purchase RAM in a set of (4) vs individual DIMMs and I was wondering if this same logic would apply to spark plugs? The issue with RAM would be that the timings, latency and speed would be different and this gave me the idea of the spark plug resistance differences.
  3. Would Spark #2 wear out faster than the rest as the resistance is the lowest out of all of them? If that happens, then what is the effect on the vehicle/ignition coil/spark plug cylinder?
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1/27 Update: Resistance Values for NGK 9124 (OEM: PE5R-18-110) (RockAuto)

@yrwei52 Here's the resistance values you requested for.

From Left to Right (In-Order)/kΩ:
  1. Spark 1: 0.428 - 0.429
  2. Spark 2: 0.404 - 0.405
  3. Spark 3: 0.418 - 0.421
  4. Spark 4: 0.545 - 0.549
I believe you meant (in KΩ):
  1. Spark 1: 4.28 ~ 4.29
  2. Spark 2: 4.04 ~ 4.05
  3. Spark 3: 4.18 ~ 4.21
  4. Spark 4: 5.45 ~ 5.49

Based on the measurements, all of my (4) spark plugs from RockAuto fall within the specifications that Mazda has listed. I will probably be measuring the Ruthenium's once I swap it out sometime this week or whenever I have a chance. The alligator clips seriously help and I can't recommend them enough. It's less than $3 with the 20% off coupon.


Questions/Observations:
  1. Should the resistance between all of these plugs be this much, especially Spark #4?
  2. Does it make a difference if I bought these plugs as a set of (4) vs individual spark plugs for the same type? For example, for desktop memory, it's recommended to purchase RAM in a set of (4) vs individual DIMMs and I was wondering if this same logic would apply to spark plugs? The issue with RAM would be that the timings, latency and speed would be different and this gave me the idea of the spark plug resistance differences.
  3. Would Spark #2 wear out faster than the rest as the resistance is the lowest out of all of them? If that happens, then what is the effect on the vehicle/ignition coil?
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1. All 4 NGK plugs are within specification 3.0 ~ 7.5 KΩ @ 77°F. As long as your room temperature is approximately 77°F, these new NGK plugs should be fine.

2. Ideally all 4 spark plugs should have identical resistance. And those new spark plugs coming with a 4-pack should have better chance with exact same specs and similar resistance as they most likely come from the same production batch. Yes computer mother board needs more specific specs on SIMMs so getting the same pack for multiple SIMM modules sometimes is necessary. Spark plugs on ICE engines the spec is not that critical. And the resistance range is wide.

3. No, I don’t believe your #2 with lowest resistance will wear out faster than others.
 
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