I really like my CX5 Touring, now at ~ 65,000 miles and was comparing the Turbo version with the RDX and other turbos vehicles. I was surprised that most suggest the first Tune-up at 100,000 miles for spark plugs while MAZDA is at 40,000 miles. Since most drivers will have the plugs changed instead of DIY, that will be a sore point. I'm courous if MAZDA will reevaluate this after they get some additional driver data? Ed
High maintenance on Turbo
- Thread starter erhayes
- Start date
The spark plugs for the 2.5 turbo are currently ~$15 each if you look around a bit. That will likely come down a bit once more of these engines get on the road. This is an inline 4, transversely mounted - changing plugs on this engine is a trivial job to do yourself. There are videos on YouTube. So, we are looking at an extra 2.5 spark plug changes or $150 and a couple hours of your time.
I would not let an additional $150 in scheduled maintenance be the deciding factor between a turbo Mazda and another brand.
I would not let an additional $150 in scheduled maintenance be the deciding factor between a turbo Mazda and another brand.
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- Plano, Texas, USA
No, Mazda won’t.
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- Plano, Texas, USA
~$15 each is the after-market NGK spark plug. The Mazda OEM PY8V-18-110 spark plug is $32.37 MSRP each and that’s the price you’d get charged, if not higher, on parts when you bring the CX-5 to a Mazda dealer for spark plug replacement. Some have insisted, including a person from Orangevirus Tuning (OVT), that we have to use Mazda OEM spark plugs on SkyActiv-G, not aftermarket ones.
Of course erhayes’ question was why everybody else on turbo has 100,000-mile spark plug replacement interval, but Mazda’s 2.5T has such a short 40,000-mile interval? Why everybody else can but Mazda can’t?
The real NGK OEM equivalent, with the matching part number, is now listed on NGK's website for $16.13, in stock, ready to ship. I'm sure the extra $16 for the Mazda logo is money well spent.
Nobody on this forum has any idea why the interval is so short, or if they do, they aren't sharing.
Nobody on this forum has any idea why the interval is so short, or if they do, they aren't sharing.
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- Plano, Texas, USA
I'm sure a person from Orangevirus Tuning (OVT) knows a lot more proprietary information than us on OEM spark plugs used on SkyActiv-G’s. His statement definitely tells us that the extra $16 on OEM spark plug simply is not just for the “Mazda” logo!
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- Canada
Spark plug DIY (on a CX-9, but same engine):
Somewhere in the comments, a user mentions the reason for the 40k interval has something to do with the high (for a turbo engine) compression ratio of 10.5:1. Obviously we'd have to take that with a huge grain of salt because its just coming from some random user in the comment section of a YouTube video, but it's something that could be verified or debunked by an inquiry sent to Mazda.
Somewhere in the comments, a user mentions the reason for the 40k interval has something to do with the high (for a turbo engine) compression ratio of 10.5:1. Obviously we'd have to take that with a huge grain of salt because its just coming from some random user in the comment section of a YouTube video, but it's something that could be verified or debunked by an inquiry sent to Mazda.
I think it has something to do with Mazda's engine management using the plugs as an additional sensor to monitor the combustion quality, like the OVT guy was saying. I had a Saab many years ago that did with their Trionic engine management, and others probably do/did something similar, so the OVT guy claiming this is some proprietary magic is dubious. By measuring the resistance across the plug gap as the combustion process occurs, you can get an idea of the gas composition across the plug gap. The downside is that this process can chew up the electrodes if you are actually discharging an additional spark, and the resistance increases as the gap opens, so you need to replace the plugs more often to keep the gap consistent.
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- Canada
Interesting.. also in the comments there are a couple of guys with 120k miles and 145k miles (as of 1 year ago).
The guy with 120k changed his plugs twice, once at 60k and once at 120k. Also, he has never changed his brake pads or rotors, but mostly does highway driving using the MRCC. Also, he mentions that he has never changed the transmission fluid.
The guy with 145k has never changed his spark plugs and according to him, he is still getting the same mileage/power. He also said he changed the original brake pads at 16k (lots of squealing), and has been on the replacement set ever since.
The guy with 120k changed his plugs twice, once at 60k and once at 120k. Also, he has never changed his brake pads or rotors, but mostly does highway driving using the MRCC. Also, he mentions that he has never changed the transmission fluid.
The guy with 145k has never changed his spark plugs and according to him, he is still getting the same mileage/power. He also said he changed the original brake pads at 16k (lots of squealing), and has been on the replacement set ever since.
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- Canada
Just found a more recent comment from the guy who had 145k. He posted about a month ago. Username is "troyrig". Here's his comment:
"I have a 2016 GT - Currently it's 4 years, 3 months and 190k miles. I just now replaced struts and shocks, sway bar links and first set of spark plugs. Otherwise it's just been oil, brake pads and tires. I switched to premium fuel at 100k miles - 25hp boost and slightly better mileage. The increase in efficiency offsets the cost so you get the horsepower boost for free, depending on the market you live in. I could go on, but I'll just say the thing is a tank."
I clarified with him and he said he replaced the original plugs with OEM plugs at 190k, and he has not noticed any difference in mileage or power since swapping.
edit - found another comment from the same user who says he's always been using conventional oil and does 5k oil change intervals.
"I have a 2016 GT - Currently it's 4 years, 3 months and 190k miles. I just now replaced struts and shocks, sway bar links and first set of spark plugs. Otherwise it's just been oil, brake pads and tires. I switched to premium fuel at 100k miles - 25hp boost and slightly better mileage. The increase in efficiency offsets the cost so you get the horsepower boost for free, depending on the market you live in. I could go on, but I'll just say the thing is a tank."
I clarified with him and he said he replaced the original plugs with OEM plugs at 190k, and he has not noticed any difference in mileage or power since swapping.
edit - found another comment from the same user who says he's always been using conventional oil and does 5k oil change intervals.
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Mazda may just be more conservative with intervals than other manufacturers. Ford and Mazda don't agree on the interval for the V6 in the old CX-9 for example. Ford says 100k, Mazda says 60k. It's the same engine. When I pulled the plugs at 60k they looked fine.
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- 2019 CX-5 GTR
@yrwei52
getting a bit off topic.. but the NGK parts finder does list NGK DILKAR7M8 as OE part for the 2.5L turbo engine.
@jal142 thanks for the heads up, not sure how recent this change is, as it was speculation previously.
getting a bit off topic.. but the NGK parts finder does list NGK DILKAR7M8 as OE part for the 2.5L turbo engine.
@jal142 thanks for the heads up, not sure how recent this change is, as it was speculation previously.
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- CX5 GT
I remember when iridium plugs were 'a thing' in 2007 they used to come with 100k kms time to change notice (back in Europe). Thats roughly 60k miles.
For Turbo cars based on my experience they lasted shorter periods.
I am guessing Mazda is just conservative and thats why it suggests 40k for the Turbo.
Also remember these are Direct injection engine nowadays. May be that plays a role too.
Actually new spark plugs do make a difference and are important part to change on time and even earlier + they are not that costly.
For Turbo cars based on my experience they lasted shorter periods.
I am guessing Mazda is just conservative and thats why it suggests 40k for the Turbo.
Also remember these are Direct injection engine nowadays. May be that plays a role too.
Actually new spark plugs do make a difference and are important part to change on time and even earlier + they are not that costly.
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- CX5 GT
yes, true and I understand that.
but that same driver would probably pay 60-80 for cabin filter and similar price for an air filter change.
and yes it adds to the total 'per mile' cost of the car in the period of ownership.
but surely we can agree the spark plugs are more important than a cabin filter and vital for the car everyday use and probably fuel economy and co2 as well. it is a maintenance part at the end of the day, same as oil and filters and tires.
just a thought but earlier spark plug change by Mazda could also be related to the high compression and the fact the engine is made to run also on lower grade fuel.
and some food for thought,
What would be the condition of the plugs for the two scenarios below
1) car driven longer distances on regular basis, proper warm up, decent rpms.
2) car driven 2-3 miles a day, lots of idling, always cold and not enough warmup for the engine and low revs.
Which one's plugs will foul at 40k?
but that same driver would probably pay 60-80 for cabin filter and similar price for an air filter change.
and yes it adds to the total 'per mile' cost of the car in the period of ownership.
but surely we can agree the spark plugs are more important than a cabin filter and vital for the car everyday use and probably fuel economy and co2 as well. it is a maintenance part at the end of the day, same as oil and filters and tires.
just a thought but earlier spark plug change by Mazda could also be related to the high compression and the fact the engine is made to run also on lower grade fuel.
and some food for thought,
What would be the condition of the plugs for the two scenarios below
1) car driven longer distances on regular basis, proper warm up, decent rpms.
2) car driven 2-3 miles a day, lots of idling, always cold and not enough warmup for the engine and low revs.
Which one's plugs will foul at 40k?
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So, at worst, it's an extra $160 every 75,000 miles compared to the non-turbo version since the normally aspirated engine schedule calls for changes at that frequency. This really doesn't seem like a deal breaker to me, especially since most people know they are going to spend more on gas and insurance stepping up to a more powerful motor.
