Spark plug replacement surprise

With the Denso's electrodes extending further into the combustion chamber, they should have a better flamefront. And the extra nub on the ground electrode should encourage more fresh charge at the area of the spark. IOW, there would be more boundary layer old charge on the NGK's ground electrode.
 
Thanks, as I stated, been there, done that, and prefer the NGK (OEM) plugs. The price difference on 4 plugs is only around $30 right now.

Try the Densos if you like and let us know what you think as more data points are always good.

With the Denso's electrodes extending further into the combustion chamber, they should have a better flamefront. And the extra nub on the ground electrode should encourage more fresh charge at the area of the spark. IOW, there would be more boundary layer old charge on the NGK's ground electrode.

Both should last 70k miles. The design between the two begs the question...Do the OEM plugs have tips or no tips?
 
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Both should last 70k miles. The design between the two begs the question...Do the OEM plugs have tips or no tips?
OEM PE5R-18-110 Mazda spark plug seems to have little difference with NGK LKAR7L11 plug in addition to "MAZDA" logo on it.

Spark plug structure looked identical although there seemed to be some different metal coloring on OEM. I was so mad they sent me NGK, I really didn't look at them much beyond wrapping and shipping back!
I did not trust myself to drop the pan and seal - so I had a mechanic do it. It took him some time. The fluid looked worn, but not burnt. I can't comment on color.
I suspect it was under filled from factory. I bought 2 bottle per recommendation on this forum. I chose the more expensive lube since I will not do this same service until 150k and judging how the car was running - that's about the limit. IMO of course.

Parts breakdown from mazdastuff.com (please note they corrected the spark plug mixup right away)

0000-77-SG1-QT Mazda Genuine Part Number 0000-77-SG1-QT | Lng Life Hyp Gear Oil Sg1
2 $21.56 $43.12

PE5R-18-110 Mazda Genuine Part Number PE5R-18-110 | Plug,Spark
4 $22.88 $91.52

9956-41-400 Mazda Genuine Part Number 9956-41-400 | Gasket
2 $0.84 $1.68

0000-FZ-113E-01 Mazda Genuine Part Number 0000-FZ-113E-01 | Atf Type-Fz
6 $10.72 $64.32

FZ01-21-500 Mazda Genuine Part Number FZ01-21-500 | Strainer,Oil
1 $27.56
 
I just hope this will be the last vehicle I ever have to worry about changing plugs on(not that it's hard by any means). But I'm going diesel as the next vehicle, so won't have to worry about plugs anymore! I am anxiously awaiting the CX-5 diesel! Finally a diesel in a vehicle that I can afford and like driving! Was hoping to get a F-150 diesel, but they will be waaaaaay out of most people's(including mine) price range. Unfortunate new trucks cost soooo much money!
My theory is that the truck has shifted from "a tool" to "a status symbol" in today's society. Used to be, it mattered about toughness, etc. and noone cared about what color the cross-stitching in the leather (or if it had pleather) seating was. Now days, noone takes their trucks off road, noone throws t-post in the back. They take them to their suburban homes and then to town to their IT jobs. Essentially, it's a BMW 3 or 5 series "with a rugged look". Thus...the cost has gotten stoopid, just like the BMW option packages.

Now, mind you, you can still get a real truck.

https://www.ford.com/new-commercial-trucks/
 
Ordered the Denso 4711's but now having doubts if I should've taken heed the words from our friend OV Virus and others. The OEM plugs are far more expensive but were literally one-off designed for Skyactiv engines. The ion sensing part sort of concerns a me. That said user install error of new plugs has to be taken into account too. Incorrectly applying dielectric grease on the plug's metal portion comes to mind.

http://www.mcx5.org/ion_sensor-1281.html
 
Ordered the Denso 4711's but now having doubts if I should've taken heed the words from our friend OV Virus and others. The OEM plugs are far more expensive but were literally one-off designed for Skyactiv engines. The ion sensing part sort of concerns a me. That said user install error of new plugs has to be taken into account too. Incorrectly applying dielectric grease on the plug's metal portion comes to mind.

http://www.mcx5.org/ion_sensor-1281.html
I almost forgot that our friend from OV Virus suggested us to use OEM plugs only on our SkyActiv gasoline engines. Anyway I'd spend $91.52 for 4 OEM replacement spark plugs when my time comes. Trying to save $50 on this once for every 75K miles is not worth it to me. I can skip a nice dinner and get this money back easily. :)
 
I almost forgot that our friend from OV Virus suggested us to use OEM plugs only on our SkyActiv gasoline engines. Anyway I'd spend $91.52 for 4 OEM replacement spark plugs when my time comes. Trying to save $50 on this once for every 75K miles is not worth it to me. I can skip a nice dinner and get this money back easily. :)

Decided to return my aftermarket plugs. Going to go with OEM's via local dealer or through Med Mazda in the near future. A bit too much proprietary tech in the skyactiv engine for me to deviate from OEM spark plugs. Ion sensing technology and all.


Pretty cool vid or spark plugs under different rpms:

https://www.youtube.com/watch?v=W8V0ULlWBrM
 
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My guess is that the O.G. :) Skyactiv engine aka the 2.0 came stock with the original part# PE01-18-110 spark plug....which is more of the Denso TT 4711 design BUT IS NOT the same part. Although they physically look the same the gap spec are different. The original part# PE01-18-110 had the smallest gaps (0.030—0.043 in) of ANY spark plugs for skyactiv engines.

....See I did not catch onto this until later on when people started pulling out their OEM plugs from their Skyactiv engines. Some had dual tips and some had one tip. Let me further elaborate. Okay Follow me on this.

Later the PE01-18-110 became obsolete (I say this because I can't find a dealership that sells it ) and were later replaced with other part numbers; the current part number being PE5R-18-110. Now the PE5R-18-110 if I'm correct looks like the NGK 94124. Both the current OEM part # PE5R-18-110 and the NGK 94124 have gaps at the wider end of the acceptable spec range (aprox. 0.044) for skyactiv engines. Thus are my opinions.


The PE01-18-110 should last longer maybe 80-100k miles. (Can't find these anywhere. Then again perhaps Mazda feels the later versions work better for skyactiv engines?)

PE5R-18-110, NGK 94124, Denso TT 4711's all have a shorter life span only due to their gaps being already wider when new compared to the original PE01-18-110.

Can't judge spark plugs simply by how clean or dirty it looks. Have to check if the gaps are out of spec too!

The NGK 94124's and the Bosch 9621's are looking appealing. They physically look like and have closer specs to the current PE5R-18-110. Not to mention cheaper.

Still debating if I should get the OEM PE5R-18-110. If so I'm getting it through Med Center Mazda.
 
...PE5R-18-110, NGK 94124, Denso TT 4711's all have a shorter life span only due to their gaps being already wider when new compared to the original PE01-18-110.

Gap size has little to do with plug lifespans unless you're way out of the gap spec and overheat or foul the plugs. Frankly, out of spec wide gaps will likely burn out your coils or throw a code before the plugs failed. I agree that there is confusion in the service manual between gaps used in the 2.0/2,5l engines. I recommend people pull a factory plug out of their own car first and inspect the current gap to decide what they would like to use.

The NGK 94124 is the OEM plug you will get when you buy a Mazda plug for a CX-5 with a 2.5L engine and have worked well for me. They come pre-gapped at .044". Many will warn against adjusting the gap on these plugs, but that's because people don't know how to safely open a gap on a precious metal plug - you grip the SIDES of the ground electrode to open it and use the tap method to close it. Of course you also need to be careful with your gauge.

I ALWAYS check the gap on plugs and did adjust my NGK's as they were ever so slightly too wide a gap out of the box for my picky eyes. Since gaps normally open as the electrodes wear away and thermal effects occur, you should err on the side of too close a gap. Keep in mind when I am talking about too close, I mean tiny differences of .001" or .1mm that still fall within the range specified in the service manual.
 
I found the gap size differences do not correspond to 2.0 vs 2.5l engines. Essentially Mazda over time changed their OEM plug specs and part numbers. I just changed my spark plugs yesterday. Here are my findings.

2013 CX-5 2.0 engine @73000 miles.

Plug Pulled: OEM PE5S-18-110 (specs)
Standard: 1.051.40 mm {0.04140.0551 in}
Tip style: Twin tipped. (Denso TT style)
Condition: Twin tips had white residue on them. Then I again I live in the desert where temps get really hot. Otherwise the plugs were in good "aged" condition and clean overall.

I was expecting to pull PE01-18-110/PE02-18-110 plugs out (with smaller gaps.) Nope. PE5S-18-110's with gaps more like aftermarket plugs.

So I installed 4 x NGK 94124 plugs from O'Reilly's Auto Parts considering they have a good return policy. Used cotton swabs to apply a thin coat of dielectric grease to the inside of rubber boots. Really small amount of anti-seize to new plugs. Carefully cleaned the coil cover rubber seals and surrounding areas of the engine cover from dirt.

I also cleaned my MAF sensor with electrical connection cleaner spray for the first time. I cleaned my AEM drop in filter again with last time cleaned 3k miles ago yet still tapped a good amount of dirt out. MAF was actually really clean considering I'm using the AEM filter which allows more air in while living in dusty conditions. Really happy with the AEM filter's protection.

Results: Really satisfied. Really smooth idle with and without AC on. Noticeable difference in torque/power from 3k-5k with and without AC on. The 2.0 is back to its happy revving self again.

Next related project: Cleaning the throttle body and maybe a bottle of Techron to gas tank followed by a 600-mile round trip prior to next oil change.
 
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I'm here to share my information aswell.

2014 CX-5 2.0 engine @52000 miles.

Plug pulled: Mazda ILKAR7L 11 (it says it on the spark plug..)
Replaced with: NGK ILKAR7L 11 (paid $25.15 a piece in The Netherlands).

Replaced oil and oil filter with EDGE 0W20 V with original OEM oil filter.

Did a small test drive for 30 kms and it feels great.

Took some pictures aswell, maybe someone can comment on it? Car ran mostly on RON95 fuel.

You can click the picture to enlarge it.

 
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Did mine as well (2014 Grand Touring AWD, 2.5L). Here's how they looked after nearly 5 years and 60k miles:

nvylkUX.jpg


more at: https://www.mazdas247.com/forum/showthread.php?123864800-2014-Touring-FWD-Spark-Plug-Model-Number&p=6594551&viewfull=1#post6594551
 
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Is that some oil on two of them?
Yes, plug on the bottom is the leftmost cylinder (#1?) and top is rightmost (#4? closest to battery). Not that surprising, seen that in lots of plugs several cars I've done over the years. I'm no expert but my gut feeling is that these high compression ratio engines take a toll on these parts. I've seen similar residue on plugs from turbocharged engines (I know there is no turbo here, but similarly high compression ratio).
 
⋯ So my warning to you is:
1) You most likely will need to buy a new 9/16" spark plug socket because your 5/8" one is too big.
Yep the traditional 13/16" and 5/8" spark plug sockets are too big. Actually the official size of spark plug socket for our CX-5 SkyActiv-G is 14 mm in metric, not 9/16"!

2) When you shop you may be told to buy the wrong size spark plug. You want a 12mm thread size, NOT a 14mm thread size. I shopped online at various national retail chains and got mixed results. Some selected a correctly sized plug (Champion and Denso are the only ones I could find) and some sites selected a too large plug. One site told presented me with both 12mm and 14mm options.
Just go for more expensive OEM PE5R-18-110 spark plugs with no worries.

My OEM plugs are the Mazda PE0118110.
Another member regtor has Mazda PE5S-18-110 plugs on his 2014 CX-5 GT AWD from factory.
 
Is that some oil on two of them?
Yes, plug on the bottom is the leftmost cylinder (#1?) and top is rightmost (#4? closest to battery). Not that surprising, seen that in lots of plugs several cars I've done over the years. I'm no expert but my gut feeling is that these high compression ratio engines take a toll on these parts. I've seen similar residue on plugs from turbocharged engines (I know there is no turbo here, but similarly high compression ratio).
Yes leftmost cylinder is cylinder #1 and rightmost, closest to battery, is cylinder #4.

Now I can't help to think about spark plug fouling issue which will be getting worse by new cylinder deactivation "feature" with cylinder #1 and #4 deactivated! (boom07)
 
A little concerned since the only vehicles with plugs like that in my driving life have been mechanical problems...
 
yep.. oil catch can/higher rpms to minimize that. never have oil on my plugs
 
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