Cylinder Deactivation Update

…. I canceled my purchase of a new 2018 CX-5 GT AWD when I learned Mazda featured the CD for 2018 CX-5 without any prior advertisements and announcements. ...
I understand that you would not want CD, and that caused you to cancel the purchase. However, I can't see why Mazda would want to advertise or promote CD as a selling point. Very few customers would have the slightest interest about an internal engine change that gives a tiny fuel savings, with no associated performance gain. Yes, the people on this thread do care a lot about such things, but the majority of buyers these days typically just consider their vehicle to be a travelling phone and audio system (and probably video for some as well). And that's what they want the automakers to tell them about.

I certainly agree with you about CD, and would MUCH rather prefer that our vehicles did not have CD, or anything else that potentially decreases reliability and increases ownership cost. But as an owner who is stuck with it, the bottom line on this for me is how Mazda handles any future CD-related issues going forward. They apparently believed the ECM programming was the issue, and fairly quickly implemented a recall of quite a few 2018-19 vehicles, and also presumably did the same fix to the 2020's before they were sold. That the automaker took this step voluntarily and proactively is IMO a green check mark for them.

Now we certainly don't know yet if the computer programming change was a completely successful solution to the problem. And there won't be an answer to that question forthcoming until enough additional time passes, and subsequent CD issues either start showing up, or (hopefully) do not.

If significant additional engine problems do begin happening (CD or otherwise), then it will fall back on Mazda to do the right thing, and cover those issues with an extended warranty. Hopefully they have already diagnosed and evaluated this correctly, making any further action unnecessary. But if subsequent problems do happen, and they try to bail on their responsibility, then that's when they lose me as a customer.
 
Will the 2021 CX5 non turbo have the cylinder deactivation?

Yes it does.

The proper way I think is to increase the engine warranty to something like 7y/100k miles. In reality any good quality build engine should last at least that long if maintained accordingly. Then myself and I guess many others will regain the confidence.

Me as a customer, I am not very happy.
I had to go 3 times already for stupid warranty issues all related to the engine (one was the cd update). Thankfully my dealer is great and all was sorted out, but still ..3 times for the engine in 2 years on a new car.
not even counting the belt tensioner.
 
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I sure hope Mazda can admit their mistake by using historically problematic cylinder deactivation with concept flaws, and quickly remove this feature from the lineups.

BTW, the improvement on US EPA fuel economy ratings for CX-5 with CD is 0~1 mpg.


Well, Mazda lost me as a customer. I canceled my purchase of a new 2018 CX-5 GT AWD when I learned Mazda featured the CD for 2018 CX-5 without any prior advertisements and announcements.

Like the big mistake by Mazda North American Operations trying to have 2.2L diesel in the US market, this’s another big mistake which would cost Mazda millions of dollars and lost of many customers. Someone higher up in Mazda Corporate should be responsible for both of these.

And I got feeling the third big mistake by Mazda is coming, the SkyActiv-X ⋯

Yea you should see on the German CX-30 forum with the SkyActiv X, alot of them are having to have a modified super charger installed in place of the old one as the one from the factory is failing and causing "Chewbacca" noise as the Germans were saying.
 
I understand that you would not want CD, and that caused you to cancel the purchase. However, I can't see why Mazda would want to advertise or promote CD as a selling point. Very few customers would have the slightest interest about an internal engine change that gives a tiny fuel savings, with no associated performance gain. Yes, the people on this thread do care a lot about such things, but the majority of buyers these days typically just consider their vehicle to be a travelling phone and audio system (and probably video for some as well). And that's what they want the automakers to tell them about.

I certainly agree with you about CD, and would MUCH rather prefer that our vehicles did not have CD, or anything else that potentially decreases reliability and increases ownership cost. But as an owner who is stuck with it, the bottom line on this for me is how Mazda handles any future CD-related issues going forward. They apparently believed the ECM programming was the issue, and fairly quickly implemented a recall of quite a few 2018-19 vehicles, and also presumably did the same fix to the 2020's before they were sold. That the automaker took this step voluntarily and proactively is IMO a green check mark for them.

Now we certainly don't know yet if the computer programming change was a completely successful solution to the problem. And there won't be an answer to that question forthcoming until enough additional time passes, and subsequent CD issues either start showing up, or (hopefully) do not.

If significant additional engine problems do begin happening (CD or otherwise), then it will fall back on Mazda to do the right thing, and cover those issues with an extended warranty. Hopefully they have already diagnosed and evaluated this correctly, making any further action unnecessary. But if subsequent problems do happen, and they try to bail on their responsibility, then that's when they lose me as a customer.
This is a good attitude to have. If it works properly and doesn't cause anymore issues for, I will be happy.
 

They apparently believed the ECM programming was the issue, and fairly quickly implemented a recall of quite a few 2018-19 vehicles, and also presumably did the same fix to the 2020's before they were sold. That the automaker took this step voluntarily and proactively is IMO a green check mark for them.
Dangerous cylinder deactivation trouble on 2018 CX-5 and 6 models

If you read the above topic started by Go Hawks on 5/3/2019, he couldn’t get any info about the problem on his 2018 CX-5 GT after 7 months of repeated tries to Mazda hence he came over here created the thread more than a year ago hopefully someone else wouldn’t encounter similar dangerous situation he and his wife had experienced in Nov. 2018 which could have killed them while passing. Not until Jul. 2019 Mazda North American Operations finally issued the safety recall on cylinder deactivation with a software fix. I believe Go Hawks wouldn’t agree with you that the Mazda took this recall step voluntarily and proactively, and was quick enough.
 
Dangerous cylinder deactivation trouble on 2018 CX-5 and 6 models

If you read the above topic started by Go Hawks on 5/3/2019, he couldn’t get any info about the problem on his 2018 CX-5 GT after 7 months of repeated tries to Mazda hence he came over here created the thread more than a year ago hopefully someone else wouldn’t encounter similar dangerous situation he and his wife had experienced in Nov. 2018 which could have killed them while passing. Not until Jul. 2019 Mazda North American Operations finally issued the safety recall on cylinder deactivation with a software fix. I believe Go Hawks wouldn’t agree with you that the Mazda took this recall step voluntarily and proactively, and was quick enough.

It takes time to identify the cause of an issue and develop a solution. Additionally you can't just issue a recall because a few people reported an issue. You need to investigate each case individually and determine a course of action. I won't pretend to know how long such an investigation might take as I'm not in this specific industry, but I do have experience with issuing service bulletins and recalls/campaigns for agricultural equipment (tractors), and it is definitely not an overnight thing.
 
…. If you read the above topic started by Go Hawks on 5/3/2019 ….
Actually I recently read that entire thread (skimming past the off-topic posting), and I give Go Hawks and the other contributors FULL credit for putting in so much time in creating such an important and helpful thread. It's certainly one of the top threads I've ever seen in all my years of participating in auto forums. And I can fully appreciate where Go Hawks is coming from, and how unsettling and upsetting this was for him and his family.

That said, IMO one needs to consider the difficulty the automaker has in trying to diagnose and resolve an issue like this one. After reading through everything related to the detached rocker arm issue, it sounds to me that the problem can only happen when a vehicle has cylinders deactivated, and the driver very quickly goes WOT (or close to it). That sequence of events provides the conditions (i.e. rocker arm unsupported on both ends) which allows the arm to fall out of position. And (again IMO) the arm detaching is probably an unpredictable and erratic event, and almost certainly difficult to consistently reproduce during testing.

So I'm guessing that Mazda probably did take Go Hawks claim seriously, but likely had a very difficult time fully diagnosing, and then creating and fully testing the reprogramming. However, once they felt confident about their fix, it seems to me that they rolled it out in a comprehensive and timely manner.

If you read my reply and believe I'm just another Mazda fanboy, be advised that I am not. I always call em as I see em - no exceptions. My daily driver for 10 years has been a Kia, and I've been a keen and close observer over the past few years of the Hyundia/Kia Theta engine nightmare/debacle, so I'm very familiar with lots of automobile owners running around with their hair on fire. And in the case of the Theta, the problem has basically lasted for 9 years, during which time Hyundai/Kia has never given an honest answer about the problem cause(s), and to this day the general public doesn't even know if it was ever truly fixed. (but one clue is that they are abandoning the Theta and replacing it with other engines).

So when I compare how Mazda has handled this CD issue (so far), to the actions of Hyundai/Kia with the Theta, it's like night and day to me. However, I will continue to keep a VERY close watch on everything related to this CD issue, and will have no problem or hesitation changing my currently positive opinion of Mazda, should that ever become necessary.
 
It takes time to identify the cause of an issue and develop a solution. Additionally you can't just issue a recall because a few people reported an issue. You need to investigate each case individually and determine a course of action. I won't pretend to know how long such an investigation might take as I'm not in this specific industry, but I do have experience with issuing service bulletins and recalls/campaigns for agricultural equipment (tractors), and it is definitely not an overnight thing.
Apparently you didn’t follow the thread closely. Go Hawks got his 2018 CX-5 fixed with a new engine and an updated PCM. At the time of Black Friday 2018 he was wondering why Mazda doesn’t update all PCM’s for CX-5 as the problem they experienced is dangerous and the fix is there. He’d been communicating with Mazda North American Operations to express the safety concerns but he got no where.

In Jan. 2016 NHTSA ordered Mazda to stop selling the CX-5 because they found a safety problem on fuel filler pipe during the rear-end collision. Mazda came up a solution within 2 weeks with a safety recall and had the stop-sale restriction removed. In cylinder deactivation case it took 8 months to come up a recall after they already had a fix?
 
Apparently you didn’t follow the thread closely. Go Hawks got his 2018 CX-5 fixed with a new engine and an updated PCM. At the time of Black Friday 2018 he was wondering why Mazda doesn’t update all PCM’s for CX-5 as the problem they experienced is dangerous and the fix is there. He’d been communicating with Mazda North American Operations to express the safety concerns but he got no where.

In Jan. 2016 NHTSA ordered Mazda to stop selling the CX-5 because they found a safety problem on fuel filler pipe during the rear-end collision. Mazda came up a solution within 2 weeks with a safety recall and had the stop-sale restriction removed. In cylinder deactivation case it took 8 months to come up a recall after they already had a fix?

Apparently yrwei52 has all the answers. Mazda should just hire him (if they can afford him) ;)

All jokes aside, the fix for the 2016 recall was a simple modification of the hardware. Modification of the hardware for the CD recall would likely have been MUCH more involved, so it would make sense for them (Mazda) to take some time to research other possible solutions. Also, risk of explosion > chance of power loss. One is more serious than the other, which would help to explain why a stop sale was issued for the recall in 2016 while a stop sale was not issued for the CD recall.

As I mentioned earlier, each recall campaign should be approached on a case-by-case basis. In the case of the CD issue, it started as a bulletin that was referenced if owners were experiencing the issue. It was then changed to a recall to preemptively update the software and get ahead of the issue.
 

All jokes aside, the fix for the 2016 recall was a simple modification of the hardware. Modification of the hardware for the CD recall would likely have been MUCH more involved, so it would make sense for them (Mazda) to take some time to research other possible solutions.
Yes, CD problem can be more complicate but that’s what Mazda wanted to get into such system with minimum benefit. At the time in Nov. 2018 when Go Hawks encountered the dangerous situation, sudden unexpected loss of power while passing, Mazda already had a fix on PCM. That’s why Go Hawks couldn’t understand why Mazda didn’t want to update the PCM for every CX-5 as soon as possible. Especially Mazda told Go Hawks that there’re 2 venders supplying the PCM chip, one of them used a wrong version of the software and they want to verify which one is the culprit. There’s no excuse IMO that it took 8 months to start updating the PCM from the recall, and putting those who are driving the CX-5 with cylinder deactivation in risk of danger.

Also, risk of explosion > chance of power loss. One is more serious than the other, which would help to explain why a stop sale was issued for the recall in 2016 while a stop sale was not issued for the CD recall.
No, explosion from the rear-end collision had never happened. It’s only an engineering company that was doing a rear-end collision test on a 2016 CX-5 for NHTSA had found the fuel filler pipe could be leaking fuel when the vehicle was rolled over after the rear-end collision. But the sudden loss of power under certain driving situation is life-threatening and Go Hawks and many others had experienced this dangerous situation in person. The safety recalls are issued on both cases, but the difference is fuel filler pipe issue was caught by NHTSA, hence they force Mazda to issue the recall with stop-sales; whereas CD issue has been aware by Mazda for a while, they’ve got PCM update to resolve the issue, but only initiated the safety recall after at least 8 months past for the reason only Mazfa knows.

As I mentioned earlier, each recall campaign should be approached on a case-by-case basis. In the case of the CD issue, it started as a bulletin that was referenced if owners were experiencing the issue. It was then changed to a recall to preemptively update the software and get ahead of the issue.
Again, it took at least 8 months to make a Service Alert to become a Safety Recall. Mazda was lucky that nobody got killed while passing due to sudden loss of power during this period.
 
Yes, CD problem can be more complicate but that’s what Mazda wanted to get into such system with minimum benefit. At the time in Nov. 2018 when Go Hawks encountered the dangerous situation, sudden unexpected loss of power while passing, Mazda already had a fix on PCM. That’s why Go Hawks couldn’t understand why Mazda didn’t want to update the PCM for every CX-5 as soon as possible. Especially Mazda told Go Hawks that there’re 2 venders supplying the PCM chip, one of them used a wrong version of the software and they want to verify which one is the culprit. There’s no excuse IMO that it took 8 months to start updating the PCM from the recall, and putting those who are driving the CX-5 with cylinder deactivation in risk of danger.


No, explosion from the rear-end collision had never happened. It’s only an engineering company that was doing a rear-end collision test on a 2016 CX-5 for NHTSA had found the fuel filler pipe could be leaking fuel when the vehicle was rolled over after the rear-end collision. But the sudden loss of power under certain driving situation is life-threatening and Go Hawks and many others had experienced this dangerous situation in person. The safety recalls are issued on both cases, but the difference is fuel filler pipe issue was caught by NHTSA, hence they force Mazda to issue the recall with stop-sales; whereas CD issue has been aware by Mazda for a while, they’ve got PCM update to resolve the issue, but only initiated the safety recall after at least 8 months past for the reason only Mazfa knows.


Again, it took at least 8 months to make a Service Alert to become a Safety Recall. Mazda was lucky that nobody got killed while passing due to sudden loss of power during this period.


JFC man, maybe Mazda should just hire you. You know how to do their jobs better than they do, apparently.
 
JFC man, maybe Mazda should just hire you. You know how to do their jobs better than they do, apparently.
I was only trying to speak the truth and fact as far as I know, nothing against a particular car manufacture such as Mazda. Go Hawks did the same at the time, even though some had attacked him as spreading false information against Mazda!
 
I enjoy reading the chronologies associated with recalls. This information can be found under "Associated Documents" for a recall on the NHTSA website.

Here's the chronology for one of the recalls on the 2018-2019 CX-5:

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I enjoy reading the chronologies associated with recalls. This information can be found under "Associated Documents" for a recall on the NHTSA website.

Here's the chronology for one of the recalls on the 2018-2019 CX-5:

View attachment 227863

Interesting, I didn't know chronologies were available. Thanks for the heads up!
 
I enjoy reading the chronologies associated with recalls. This information can be found under "Associated Documents" for a recall on the NHTSA website.

Here's the chronology for one of the recalls on the 2018-2019 CX-5:

View attachment 227863
Thanks for the finding. Now we know the official story from Mazda why it took 8 months since Nov. 2018 when Go Hawks encountered the incident. But in Nov. 2018 Go Hawks did receive a newer version of PCM firmware and that’s why he kept wondering why Mazda didn’t update all PCMs to prevent this dangerous situation happening to anybody else. Mazda had another design change on PCM after Nov. 2018 based on the NHTSA’s chronology. Hopefully Go Hawks did get a recall notice and had his PCM updated again if he still have the CX-5.

Interesting fact is Mazda received the first report of fallen rock arm on Jan. 31, 2018, and they didn’t find anything on it until Nov. 2, 2018 for root cause?

And I was so excited preparing to get a new 2018 CX-5 GT AWD and went to my Mazda dealer checking out just available new CX-5’s on Jan. 8, 2018. I found several new surprises which I’d been repeatedly asked for and missing on my 2016 CX-5: memory seat、one-touch open/close power windows with anti-pinch capability and illuminated switches for all windows、 and open/close dial controls on center dash vents, in addition to the biggest surprise to me, the cylinder deactivation.

A Few Surprises from US 2018 Mazda CX-5
 
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It's likely no different than Ford's decision not to initially recall Pintos or GM's delay in recalling vehicles over faulty ignition switches where the estimated payouts for injury and death claims were lower than the cost to fix the vehicles.

Of course, there are times when a problem is so elusive that it takes a sufficient number of reports and failure analyses before a pattern emerges and a reasonable fix can be formulated. Depending on the frequency of documented failures, it might take days, weeks, months, or years to find the root cause of a problem and a remedy.

Recalls are issued only for violations of Federal Motor Vehicle Safety Standards or unreasonable safety risks. There are differences in opinion about what an "unreasonable" safety risk is. Often, consumers embellish failures and spin them into safety risks. For example, I've seen Honda owners crying for Honda to issue a recall for failure of their air conditioners citing that it's a safety risk because a person could suffer heat stroke if their A/C fails. A/C is not required by any safety standard nor does its failure present an "unreasaonable" safety risk. A/C may be ubiquitous these days, but it's still a luxury and not a necessity. That noise comes from customers who experience failures after their warranties expire and are mad that they have to spend $1,000 to fix their A/C.
 
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Thanks for the finding. Now we know the official story from Mazda why it took 8 months since Nov. 2018 when Go Hawks encountered the incident. But in Nov. 2018 Go Hawks did receive a newer version of PCM firmware and that’s why he kept wondering why Mazda didn’t update all PCMs to prevent this dangerous situation happening to anybody else. Mazda had another design change on PCM after Nov. 2018 based on the NHTSA’s chronology. Hopefully Go Hawks did get a recall notice and had his PCM updated again if he still have the CX-5.

Interesting fact is Mazda received the first report of fallen rock arm on Jan. 31, 2018, and they didn’t find anything on it until Nov. 2, 2018 for root cause?

And I was so excited preparing to get a new 2018 CX-5 GT AWD and went to my Mazda dealer checking out just available new CX-5’s on Jan. 8, 2018. I found several new surprises which I’d been repeatedly asked for and missing on my 2016 CX-5: memory seat、one-touch open/close power windows with anti-pinch capability and illuminated switches for all windows、 and open/close dial controls on center dash vents, in addition to the biggest surprise to me, the cylinder deactivation.

A Few Surprises from US 2018 Mazda CX-5
Mazda announced the CD feature in 2017. Apparently you didn’t follow the Mazda specs closely.
 
I think there has to be more than just CD that made yrwei sour on Mazda. I can understand it, for example seeing how Mazda gives general fuel capacities in the manual is pretty bad.
 
Mazda announced the CD feature in 2017. Apparently you didn’t follow the Mazda specs closely.
If Mazda did announce the cylinder deactivation in 2017, either they announced very late in 2017 or they didn’t say it’d be a feature for 2018 US models. I don’t remember the CD discussion here until very late in 2017 and early 2018 in this community. See the long discussions of 2018 CX-5 I created at the time with the link in my previous post.
 
I think there has to be more than just CD that made yrwei sour on Mazda. I can understand it, for example seeing how Mazda gives general fuel capacities in the manual is pretty bad.
I still like my 2016 Mazda CX-5 GT AWD with Tech, and plan to keep it as long as I can. And I didn’t get the 2018 CX-5 as planned, but I did get a different Mazda, a 2018 Toyota Yaris iA which is a Mazda2 in disguise.

Although I personally don’t prefer those mainly due to long-term reliability concerns, but I can consider CVT、Turbo、and PHEV, as all of these features are from legit concept for something good. HCCI is a good concept, but Mazda’s SPCCI SkyActiv-X may not be as it keeps adding components to HCCI and has become too complicated for not much gain on efficiency. Cylinder deactivation IMO is a bad concept to start with, the end results can’t be good no matter how you design it and modify it. And the history has proven my believe on CD.

Yes I don’t like those approximate fluid capacities on Mazda’s specs which are inconsistent, so as the range on torque value from Mazda’s manuals. To me, these are part of the Mazda’s way trying to be different from everybody else.
 
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