NA CX-5 with Cylinder Deactivation Engine Repairs - Report In

Our powertrain warranty on our 2018 CX5 will expire in a few weeks also. They need to extend the warranty on these engines like Mazda did years ago on their rotary engines. Glad to hear they covered most of the cost for you.

How many miles on your CX5?
About 48k.
 
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Noticed a burning oil smell and took it to our mechanic.
....
They offered to pay for all but $250 which I accepted. ....
Were you able to determine if this out-of-warranty coverage is coming from Mazda Corporate, or if it's your dealer providing goodwill (or perhaps some combination of both)?

One thing about your report that's particularly interesting to me is where you mentioned 'our mechanic'. That sounds to me like you might have all of your oil changes and other routine maintenance done by that indy shop. If that's correct, then based on comments made by other owners; someone who doesn't have their vehicle serviced at the dealership is normally considered to be much less 'loyal' than those who do. Can you post back on that, if there was a discussion about it by anyone from Mazda?
 
Were you able to determine if this out-of-warranty coverage is coming from Mazda Corporate, or if it's your dealer providing goodwill (or perhaps some combination of both)?

One thing about your report that's particularly interesting to me is where you mentioned 'our mechanic'. That sounds to me like you might have all of your oil changes and other routine maintenance done by that indy shop. If that's correct, then based on comments made by other owners; someone who doesn't have their vehicle serviced at the dealership is normally considered to be much less 'loyal' than those who do. Can you post back on that, if there was a discussion about it by anyone from Mazda?
The goodwill repair is coming from Mazda.

I generally do my own oil changes and go to my local (non-Mazda) mechanic for more complicated repairs. Mazda service department did the oil changes for the first 3 years on this car.

I currently own 3 Mazdas and have purchased 7 starting with my 1985 RX-7, likely over $200,000 worth of vehicles. I've also referred several people to my dealership. Mazda Customer Experience was able to see my purchase history (at least the recent ones) while I was on the phone with them. They considered me a loyal customer.
 
The goodwill repair is coming from Mazda.

I generally do my own oil changes and go to my local (non-Mazda) mechanic for more complicated repairs. Mazda service department did the oil changes for the first 3 years on this car.

I currently own 3 Mazdas and have purchased 7 starting with my 1985 RX-7, likely over $200,000 worth of vehicles. I've also referred several people to my dealership. Mazda Customer Experience was able to see my purchase history (at least the recent ones) while I was on the phone with them. They considered me a loyal customer.
Thanks for sharing the details of your interaction with them. Although Corporate usually passes the buck back to the dealer to come up with the goodwill, in your case they apparently decided to fork over the $$, based on your purchase history. And I guess you're fortunate they did, because it sounds like your dealership had no intention of helping someone who didn't have their vehicles serviced by them (regardless of how many Mazdas you've purchased).
 
We had this problem on our 2018 CX-5 GT (normally aspirated).
Noticed a burning oil smell and took it to our mechanic. He spotted the leak at the head and told us to take it to the dealer as Mazda may cover the repair.
Took it to the dealer and found we had a cracked cylinder head. Quoted over $5,000 to repair.
We were 3 weeks past the 5 year powertrain warranty.
I called Mazda Customer Experience and told them I expect Mazda to pay for this as it is a known issue and I've been a loyal Mazda customer for decades.
They offered to pay for all but $250 which I accepted. Should have the car back this week.
I still feel they should have paid for the entire repair as it is not an isolated issue.
Thanks for reporting. But you’re on the better side as some who have the cracked head on their 2.5L NA with CD and past powertrain warranty didn’t get any help from Mazda North American Operations.
 
SA-037/23


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All this means is that the new cylinder head ordering procedure includes 2022 and 23 models. If you look up the previous SA from March 22, it only applies through 2021 models. It does not mean that they have changed anything in the design of the cylinder head.
 
So. All of these models listed above thru 2023 and are ticking time bombs and no modification has been made to the thin casting
Could this thin casting be by design? Meant to last 6 years and no more? If no effort has been made to assure it's been addressed in production one may wonder why not. Maybe a stretch but one would think those in the know would try to dispel any long term problems that may occur.
 
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I was wondering if there is any difference between Japanese and Mexican heads in terms of failure trends? I am not sure, but I think CX-30 and 3 are made in Mexico for the North American market. The CX-30 has only been around since the 2020 MY, but soon some will have high mileage examples out there, and I am not sure when the 3 got cylinder deactivation. If you look up, for example, a 2022 CX-5 then it references two cylinder heads with CD, one Mexican made and one Japanese. The notes indicate that the Mexican is for 3 and CX-30 but also fit the 2018- CX-5 and 6.

The part numbers are PYFA-10-100E (JP) and PYY4-10-SJ0 (MEX). As I reported here a few months ago, a look up for 2022 MY CX-5 yielded nothing, so the 2022 has been recently added in the database in parallel with the SA that now lists these cars through 2023 MY.

p.s. If you look up a 2023 CX-5 in the parts database you do not find any cylinder head, just like for the 2022 back in May when I looked at it last. Another puzzling thing is that the Mexican part does not list CX-5s before 2021 as being compatible......... The 6 is listed for 2018-20.
 
I was wondering if there is any difference between Japanese and Mexican heads in terms of failure trends? I am not sure, but I think CX-30 and 3 are made in Mexico for the North American market. The CX-30 has only been around since the 2020 MY, but soon some will have high mileage examples out there, and I am not sure when the 3 got cylinder deactivation. If you look up, for example, a 2022 CX-5 then it references two cylinder heads with CD, one Mexican made and one Japanese. The notes indicate that the Mexican is for 3 and CX-30 but also fit the 2018- CX-5 and 6.

The part numbers are PYFA-10-100E (JP) and PYY4-10-SJ0 (MEX). As I reported here a few months ago, a look up for 2022 MY CX-5 yielded nothing, so the 2022 has been recently added in the database in parallel with the SA that now lists these cars through 2023 MY.

p.s. If you look up a 2023 CX-5 in the parts database you do not find any cylinder head, just like for the 2022 back in May when I looked at it last. Another puzzling thing is that the Mexican part does not list CX-5s before 2021 as being compatible......... The 6 is listed for 2018-20.
Firstly mazda-parts.com is just a online seller by a Mazda dealer where the parts database on its website usually isn’t up to date. The parts department at the Mazda dealer has a totally different parts system and it has the latest and greatest parts list available. For accurate part number you really want to go to a Mazda dealer to verify with the VIN.

Based on limited info by Mazda online seller website, PYFA-10-100E and PYY4-10-SJ0 both actually cover the same 2.5L NA with CD including Mazda3、Mazda6、CX-5 under ”Vehicle Fitment”. Interestingly under PYY4-10-SJ0 it says “Replaces: PYFA-10-100F, PYY6-10-SJ0, PYY6-10-SJ0A”. My conclusion is PYY4-10-SJ0 is the latest part number for cylinder head on all 2.5L NA with CD, as it superseded PYFA-10-100F which is a newer version of PYFA-10-100E. In addition, nothing indicated PYFA-10-100E is from Japan; and PYY4-10-SJ0 is from Mexico, the only thing for sure is they’re the same cylinder head.
 
It does say "Japan built" and "Mexico built". It is not clear if it is referring to the models (likely) or the cylinder head, but there could be a link in that the Mexican built models would likely be supplied locally.

"Mazda3. Mexico built. With cyl deactivation. CX-30. Without turbo."
I guess it is actually saying that it is for the Mexico built Mazda 3 that also has CD. Then for the newer CX-30, all have CD unless a turbo model.

I am aware what mazda-parts represents. It is a dealer in Redondo Beach, CA with online discounted parts where I have shopped.

But check out parts.mazdausa.com, which then refers you to local dealers for the parts. If you enter the PYYA number then it shows that it only fits 2021-23 models, which is good news for me as a 2022 model owner and suggests an updated part. The PYFA-10-100E shows that it is compatible with 2018-20 models, so maybe was the original part. This could be an important finding and supports that 2021- models may have seen some sort of modification. This could just be the casting thickness.
 
It does say "Japan built" and "Mexico built". It is not clear if it is referring to the models (likely) or the cylinder head, but there could be a link in that the Mexican built models would likely be supplied locally.

"Mazda3. Mexico built. With cyl deactivation. CX-30. Without turbo."
I guess it is actually saying that it is for the Mexico built Mazda 3 that also has CD. Then for the newer CX-30, all have CD unless a turbo model.

I am aware what mazda-parts represents. It is a dealer in Redondo Beach, CA with online discounted parts where I have shopped.

But check out parts.mazdausa.com, which then refers you to local dealers for the parts. If you enter the PYYA number then it shows that it only fits 2021-23 models, which is good news for me as a 2022 model owner and suggests an updated part. The PYFA-10-100E shows that it is compatible with 2018-20 models, so maybe was the original part. This could be an important finding and supports that 2021- models may have seen some sort of modification. This could just be the casting thickness.
It’s more clear now that my conclusion previously was correct by this invoice fixing cracked cylinder head on a 2.5L NA with CD from a 2022 CX-5 with 13,000 miles. The invoice listed PYY4-10-SJ0, cylinder head set, which is mentioned in the Service Alert posted above. It superseded PYFA-10-100F which should be only a “bare” cylinder head with nothing installed on it.


It is still happening with the 2022 models. I just got my cylinder head replaced under warranty. It's a CX-5 with a skyactive engine; it's not the turbo. I bought it new in March of 2022 and it only has 13,000 miles on it. There were no warning signs or symptoms other than the low oil level light coming on. I have the oil changed twice a year, so that definitely shouldn't have happened. I stopped immediately so no damage was done to the engine. I hope the replacement head will last.


This in in reply to sm1ke. I think I posted a blank reply a minute ago.
 
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Oh dear. That's not good news. She said she bought it in March 22 but delivery date was June 22, so I guess a March-April 22 build date. Mine is June 22.

The PYY4-10-SJ0 was listed in the original SA from July 2020 where it was part of the 0000-99-SCX5 Head Set Kit, which has now been superseded byt the PYY4 part. So the question is if this caused by casting defects in specific heads or an inherently flawed design. I would say that someone driving nearly 14k in one year is on the highway a lot where cylinder deactivation is operating. Our car sees mostly city driving. Keep it in Sport mode to avoid cylinder deactivation?

Any idea when the PYY4 replaced the "F" or "E" part? It must have been before or latest early-mid 2020. As you point out, there was probably not any change in the actual head but just a move from offering the head to a "head set".

Maybe time to get rid of the car? It has less than 3k miles. It will be covered by the warranty over the 5 years if we keep it. But what should I replace it with??

I wish they had base models like in Australia; they even have (had) a manual trans option, which I would have been keen to get but it was primarily my wife's car. We bought a 2019 CX-5 in Australia for only about USD 18k with a 2.0 liter engine. It even had folding mirrors (although not when you lock it), which is a ultra-premium feature in the US! At the time in 2018, the CX-5 was the number one selling mid-size SUV in Australia and the 3 was the number one sedan, so they were motivated to have a very broad offering. I think they had 6 trim levels. At the time Mazda was the number one car maker there if you exclude pick-ups / utes. I looked earlier this year and the Rav 4 outsold the CX-5 in 2022 by quite a margin. In 2018 Toyota had a very ugly looking Rav 4 that was about to be replaced.

The 2.0 liter was fine. I tended to put it in sport mode to compensate.
 
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So. All of these models listed above thru 2023 and are ticking time bombs and no modification has been made to the thin casting
Could this thin casting be by design? Meant to last 6 years and no more? If no effort has been made to assure it's been addressed in production one may wonder why not. Maybe a stretch but one would think those in the know would try to dispel any long term problems that may occur.
I thought you were wrong, but this 2022 failure indicates that they are indeed "ticking time bombs".......... Time to check how much Carvana wants to cough up.;)
 
The PYY4-10-SJ0 was listed in the original SA from July 2020 where it was part of the 0000-99-SCX5 Head Set Kit, which has now been superseded byt the PYY4 part. So the question is if this caused by casting defects in specific heads or an inherently flawed design. I would say that someone driving nearly 14k in one year is on the highway a lot where cylinder deactivation is operating. Our car sees mostly city driving. Keep it in Sport mode to avoid cylinder deactivation?
If you read the original Service Alert, SA-058/20, it explained it very clearly that PYY4-10-SJ0 is the new cylinder head set which includes cylinder head, (older assembly, should be PYFA-10-100F)、valve cotter、valve SPG-UP seat、valve spring、outer-EX valve spring、inlet valve、exhaust valve. P/N 0000-99-SCX5 then includes PYY4-10-SJ0 cylinder head set and many other parts including gaskets and head bolts. In the latest SA SA-037/23 the head bolts are no longer in the parts list for head replacement, hence P/N 0000-99-SCX5 which includes head bolts may no longer been used.

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The 2.0 liter was fine. I tended to put it in sport mode to compensate.
Yes, Mazda’s original original SkyActiv-G 2.0L is the best among SkyActiv-G engines, period. It doesn’t need the heavy balance shaft found on all 2.5L’s, and it’s reliability record is excellent.

I didn’t aware the Sport Mode where Mazda started to offer from 2016 MY CX-5 is also available on the 2.0L.
 
Yes, Mazda’s original original SkyActiv-G 2.0L is the best among SkyActiv-G engines, period. It doesn’t need the heavy balance shaft found on all 2.5L’s, and it’s reliability record is excellent.

I didn’t aware the Sport Mode where Mazda started to offer from 2016 MY CX-5 is also available on the 2.0L.

With regard to your earlier post I think we are saying the same thing. And I joined the camp stating that there is no change or improvement to the cylinder head. My thinking is that with the very thin gauge shown in the Russian video, it is highly susceptible to minimal casting defects and that's the reason for the failures.

The 2.0 has not been available in the US since 2019 MY when the new 3 appeared in the US with 2.5 only. Our USD 18k (could have gotten a manual for 17k) entry level CX-5 was perfectly fine. We sold it with only 6k km on the clock last year after slightly over 3 years on the road. It had a build date of 9/2018. So last year we bought a second to entry level CX-5 in the US for 30k, and it really does not offer much more for our needs, but adds this "time bomb" feature. Sigh.........

I hope sport mode is a method to stop cylinder deactivation, but will not keep it more than 3 years at most.

Finally, I hope that they actually re-designed the CX-9 cylinder head since we also bought one of those last year.......
 
All of this extended discussion about part numbers and failure cause makes it harder to sort through the information and find the actual failure reports, which is what this thread is supposed to be about. Why not start a new thread - something like "what's the real cause of the cracked heads?". Then you can post as much of this stuff as you want to.
 
With regard to your earlier post I think we are saying the same thing. And I joined the camp stating that there is no change or improvement to the cylinder head. My thinking is that with the very thin gauge shown in the Russian video, it is highly susceptible to minimal casting defects and that's the reason for the failures.
IMO Mazda modified the original (and reliable) cylinder head on the 2.5L NA to accommodate the additional cylinder deactivation components and apparently something has compromised. I guess Mazda feels either the failure rate is still not high enough to make another design change, or they can’t figure out a better way to enhance the head.


The 2.0 has not been available in the US since 2019 MY when the new 3 appeared in the US with 2.5 only. Our USD 18k (could have gotten a manual for 17k) entry level CX-5 was perfectly fine. We sold it with only 6k km on the clock last year after slightly over 3 years on the road. It had a build date of 9/2018. So last year we bought a second to entry level CX-5 in the US for 30k, and it really does not offer much more for our needs, but adds this "time bomb" feature. Sigh.........
I have never had a good feeling on cylinder deactivation due to its design concept. It’s also been proven historically that the cylinder deactivation has been nothing but troubles since GM started to use it in 1980’s on their V8’s. I gladly canceled my purchasing plan to a 2018 CX-5 once I learned Mazda had “secretly” added the cylinder deactivation to the 2.5L NA.


I hope sport mode is a method to stop cylinder deactivation, but will not keep it more than 3 years at most.
IMO using the Sport Mode won’t help the matter. The cracked cylinder head should be caused by the thin wall as showed in the YouTube video. Even if you keep CD disabled all the time, the weak spot is still there. And the possibility of cracking is always there no matter how rare the case may be.


Finally, I hope that they actually re-designed the CX-9 cylinder head since we also bought one of those last year.......
Based on the TSB, Mazda did have redesigned the cylinder head and exhaust manifold gasket on the 2.5T. Only time will tell how effective the modification will be.
 
I'm the person who posted a couple of months ago with the 2022 CX-5 NA that had the cracked cylinder head at 13,000 miles, and posted the repair invoice. In reading all the posts since that time with the discussion of the parts numbers, if I've read those posts correctly, the consensus is that the replacement kits have the same old (possibly) defective cylinder head in them. So even though my car was repaired, it may still be a ticking time bomb?

I assume that it's still a minority of vehicles that actually have had their cylinder head crack, but if there has been no improvement to the cylinder head, why is it just a minority of us having the problem? That's really just a rhetorical question, as I'm sure no one has the answer, but any theories would be appreciated (in layman's terms, I'm not a car person).

(FYI, I actually ordered the car in April, not March as I originally said. And, as someone guessed, a lot of my mileage is highway mileage.)
 
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