Dangerous cylinder deactivation trouble on 2018 CX-5 and 6 models

Was concerned about the CD at first, but now with over 30k miles on our ‘19 (had update done around 5k), not longer worried about it. And would any day take cylinder deactivation over the incredibly-annoying stop/start that most vehicles seem to come with now.
 
:
2018 CX-5 Sport
I don't think Mazda NA even fully understands the issue, probably only a few engineers in Japan understand the condition in which the rocker can be displaced. We hear the generic answer that there wasn't enough oil pressure and guesses that revving the motor made it displace. I think the people on this forum are responsible for Mazda even issuing a recall. Only a couple hundred out of thousands of cars had the issue occur. I hope you do write to Mazda to see what they say. I think the answer will come to us as people put more miles on their cars and report issues here on this forum. Some people must be reaching 100K miles on their cars by now that have CD. Thus far no one has reported an issue here.
 

erhayes

Contributor
:
CX5 Reserve
Difficult to understand why MAZDA engineers didn't foresee this ptential problem and fix it before it was introduced to the market. Ed
 
If you re-read the original post by OP Go Hawks, he couldn’t get any info about the problem after 7 months of repeated tries. Hence 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.

Yes you can suggest TotalMazda1 trying to get more details about the issue, but IMO he won’t get anything more than things we had discussed here, may be even less.

I made the comment that I agreed with TotalMazda1‘s opinion, and suggested he won’t get anything from Mazda dealers or MNAO although he can always try.

I don’t understand someone would come up here and tell us not to discuss this issue anymore because Mazda has issued a recall and apparently has fixed the problem. TotalMazda1‘s concern is for long-term when the HLA and other related parts starting to wear out a bit and it may loose some oil pressure controlled only by the software. There’s no fail-safe hardware to prevent the falling rocker arm if the oil pressure is out of specs. The result could be a fallen control arm again.

Just because it’s been many months and there’s no reports of failure, Mazda can claim the problem has been permanently fixed. A perfect example is the rear brake EPB dragging issue. Mazda at first issued a TSB with EPB module replacement. Then again issued another TSB with another revised EPB module replacement. Both revisions were software patch job but apparently the problem were still happening from time to time. Mazda eventually revised rear brake calipers with actual hardware fix, which hopefully has really fixed the problem.
Thank the Lord that there is someone on this board that totally understands my concern. Thanks Yrwei52. Guys.... I have NOT purchased a CX5, a new one WAS on the top of my list. But, I am getting rid of a 219K mile Toyota and as you see, i keep my cars longer than 3 yr leasers do. I am in it for the long haul..... if I dont go with a 2017 CX5, I will not be one of those folks, out of warranty that Mazda denies to repair with a new engine. You other folks who have relative low miles and think your AOK....well, if you are gonna get rid of it , no prob...Thanks again Yrwei52. I will not be attempting to contact Mazda, it will just frustrate me and end up with the same findings other posters have had....no solid guaranteed answer that rocker arms wont fly off....
 

shadonoz

SkyActiv Member
Contributor
:
State of Jefferson
:
2017 CX-5 GT AWD+
Check out this description of GM's new 4 cyl with CD from one of my favorite geeks, Engineering Explained.

The entire video is informative and entertaining, but if it's tl;dw, the CD discussion begins at 3:23.

Unfortunately, he doesn't explain what's moving the cam slider.

I found the movement of the followers fascinating [4:26]. How could they not "jump the tracks" at speed without heavy down pressure and resultant wear, especially laterally?
 

sm1ke

Work In Progress..
Moderator
Contributor
:
Canada
:
'18 CX-9 Signature
Thank the Lord that there is someone on this board that totally understands my concern. Thanks Yrwei52. Guys.... I have NOT purchased a CX5, a new one WAS on the top of my list. But, I am getting rid of a 219K mile Toyota and as you see, i keep my cars longer than 3 yr leasers do. I am in it for the long haul..... if I dont go with a 2017 CX5, I will not be one of those folks, out of warranty that Mazda denies to repair with a new engine. You other folks who have relative low miles and think your AOK....well, if you are gonna get rid of it , no prob...Thanks again Yrwei52. I will not be attempting to contact Mazda, it will just frustrate me and end up with the same findings other posters have had....no solid guaranteed answer that rocker arms wont fly off....

This is the question you asked. "As the engine ages and clearances widen, whats to prevent the pressure from dropping on higher mileage engines. I intend to keep my Mazda at least 200k miles.... can anyone with an in-depth knowledge of the actual software fix respond?"

If you wanted confirmation of the condition that causes the problem, you can refer to the recall and TSB info that Mazda provided (which yrwei52 referenced).

The best you can get for this cylinder deactivation problem is the description in the related Service Alerts and TSBs posted earlier in this thread.

If you want an actual answer to the question you asked, contact Mazda directly, or maybe find a software programmer who can look into this for you. That would be your best shot at getting a proper answer. The fix applied by the recall is still fairly new, so only time will tell. yrwei52's opinion on whether the software fix is viable in the long run is just that - an opinion. It's the same opinion you have. Based on the questions you're asking, I would think that you would want more than just an opinion, thus the suggestion to contact those with more information about the CD issue (or those with the means to derive the info from the resources we have).

Otherwise, if you are still in the market for a CX-5, find a used 2017 or look for 2019-2020 GT Reserve or Signature models. Those year/model trims do not have CD.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
Check out this description of GM's new 4 cyl with CD from one of my favorite geeks, Engineering Explained.

The entire video is informative and entertaining, but if it's tl;dw, the CD discussion begins at 3:23.

Unfortunately, he doesn't explain what's moving the cam slider.

I found the movement of the followers fascinating [4:26]. How could they not "jump the tracks" at speed without heavy down pressure and resultant wear, especially laterally?
LOL! With all the complexity of 3-position camshaft and cylinder deactivation, this new GM L3B 2.7L turbo I4 designed for trucks has worse highway gas mileage at 23mpg on Silverado, whereas the standard 5.3L V8 has 24! No wonder the guy said “If you want the best fuel economy on the highway, get the V8 ⋯ Errrr”.
 
Guys, I'm about to put down a deposit for a 2020 CX-5 2.5L with CD. Given this issue happened over two years ago, I assumed this software fix would've been implemented at the factory, or the dealership would've applied it when they got the vehicle delivered to their yards.

Can you guys please post your updates on how many KM/MILES you've travelled and if the engine with CD is still running strong?
 
Last edited:
:
‘17 CX9 & ‘19 3 GT
Guys, I'm about to put down a deposit for a 2020 CX-5 2.5L with CD. Given this issue happened over two years ago, I assumed this software fix would've been implemented at the factory, or the dealership would've applied it when they got the vehicle delivered to their yards.

Can you guys please post your updates on how many KM/MILES you've travelled and if the engine with CD is still running strong?
10mos/8K kms the last reading on a Mazda 6 with the CDA and no issues...I won’t worry too much about it if you’re considering that engine as there hasn’t been any other TSB/recall after the 2019 software update. Besides, any power train issue is covered for 5yrs under warranty!
 
:
2018 CX5 GT, Metallic Machine Gray and 2018 MX-5 RF GT, Soul Red
I had the recall (3719F) rocker arm reprogram done back in July 2019. I have travelled about 16,000 km since the recall and no issue so far. I haven't seen any mention on this forum or any other about the issue arising on a CX5 that had been reprogramed. I still have another 3 years left on the power train warranty (unlimited mileage in Canada) so I am not worried. IMHO buy the CX5, relax and enjoy the ride. I certainly don't regret my CX5 purchase.

Wade
 
Thanks for the feedback. Two things I worried about this engine is 1. Carbon buildup associated with direction injection. 2. This CD recall.

From my research for past 6 months, these Skyactiv engines seem to be pretty reliable and don't exhibit the negative impacts of the above two issues like the other manufacturers.

I hope and trust Mazda engineers knew what they were doing when they designed these engines. That's why I waited for a few years for all the bugs to get ironed out first.

P.S. I was actually thinking to get the new gen 2021 Hyundai Tucson, but who knows what sort of bugs and quality control issues it has being the first model year...
 
:
‘17 CX9 & ‘19 3 GT
Thanks for the feedback. Two things I worried about this engine is 1. Carbon buildup associated with direction injection. 2. This CD recall.

From my research for past 6 months, these Skyactiv engines seem to be pretty reliable and don't exhibit the negative impacts of the above two issues like the other manufacturers.

I hope and trust Mazda engineers knew what they were doing when they designed these engines. That's why I waited for a few years for all the bugs to get ironed out first.

P.S. I was actually thinking to get the new gen 2021 Hyundai Tucson, but who knows what sort of bugs and quality control issues it has being the first model year...
I am also not worried about the carbon build up in DI engines as chances are I won’t own the vehicle for that long when the time comes there is significant carbon build up. Engine has also been reliable (the tried and true 2.5L of course without the CDA) and Mazda won’t be implementing them including their 2.5L Turbos in almost all other models except the Miata if they weren’t reliable.

Highly likely that 80% or more of Mazda owners are either not aware or aren’t worried too much about the carbon build up on DI engines just like majority of owners of Toyota’s and Hondas that use CVT trannys aren’t also aware or worried. Only the enthusiasts are really aware and knowledgeable about these things which represent a low % amongst owners. Sometimes knowing too much takes away the fun in owning and driving vehicles and rather increases the worrisome and anxieties. Driving still matters right?!
 
I am also not worried about the carbon build up in DI engines as chances are I won’t own the vehicle for that long when the time comes there is significant carbon build up. Engine has also been reliable (the tried and true 2.5L of course without the CDA) and Mazda won’t be implementing them including their 2.5L Turbos in almost all other models except the Miata if they weren’t reliable.

Highly likely that 80% or more of Mazda owners are either not aware or aren’t worried too much about the carbon build up on DI engines just like majority of owners of Toyota’s and Hondas that use CVT trannys aren’t also aware or worried. Only the enthusiasts are really aware and knowledgeable about these things which represent a low % amongst owners. Sometimes knowing too much takes away the fun in owning and driving vehicles and rather increases the worrisome and anxieties. Driving still matters right?!
Indeed you're right. Just picked up a 2020 CX-5 with CDA today. I belong to that 1% population who knows and worries too much. The average Joe would not know or care. My obsessions with these things can sometimes hinder and take the joy out of owning and enjoying it.

My wife tells me, don't get too attached and just enjoy it. "People are meant to be loved, and things such as cars are meant to be used"
 
In a separate topic, one weird thing I noticed was that under light-moderate breaking from high speed (let's say 70mph to 10mph) I noticed the rear breaks are making this "mild rumbling noise". Sounded like touk, touk, touk... as in, the ABS system is constantly kicking in even under mild breaking.

I found a section in the manual which reads "this vehicle has a power-assisted brakes that assist automatically though normal use" - could that be it?

Has anyone experienced this when they first picked up their new car? Car is only has 60 miles on it, so maybe it needs time to break in?
 
Last edited:
:
2020 CX-5 GT w/PP
In a separate topic, one weird thing I noticed was that under light-moderate breaking from high speed (let's say 70mph to 10mph) I noticed the rear breaks are making this "mild rumbling noise". Sounded like touk, touk, touk... as in, the ABS system is constantly kicking in even under mild breaking.

I found a section in the manual which reads "this vehicle has a power-assisted brakes that assist automatically though normal use" - could that be it?

Has anyone experienced this when they first picked up their new car? Car is only has 60 miles on it, so maybe it needs time to break in?
I haven't noticed that with my new 2020, but I'll listen for it over the next couple of days.
 
:
‘17 CX9 & ‘19 3 GT
Indeed you're right. Just picked up a 2020 CX-5 with CDA today. I belong to that 1% population who knows and worries too much. The average Joe would not know or care. My obsessions with these things can sometimes hinder and take the joy out of owning and enjoying it.

My wife tells me, don't get too attached and just enjoy it. "People are meant to be loved, and things such as cars are meant to be used"
Congrats on the new ride and CX-5’s a great vehicle! Totally agree with what your wife said...I myself treat my vehicles as commodities meant to serve my needs not the other way around!

One car salesman told me over 10 years ago that I will never forget that you shouldn’t be obsessing in looking for issues and faults on your new vehicle as that can consume you and take away the joy and excitement of driving it. Hence if issues arise then simply deal with it...you spent thousands and thousands of hard earned money meant to enjoy driving it and not add to your miseries. “Don’t let the little things and issues get in the way and spoil your excitement in owning the new car”!
 
1

184789

I dont doubt the events that you have listed but im not sure of the order or when the rocker fell off or if the dealer is telling the truth on that one. If the rocker was off you would notice it. That cylinder would be starved all the time. You may not notice it at idle but at 1/4 throttle and above you would. The cylinder would be down on compression and this would make the car slugish and a bit rough. Replacing the engine becausw the rocker came off doesnt make sense either. The cost of the motor and labour would be thousands compaired to just replacing the rocker and associated parts. If as you say the oil pressure was too low this could cause damage to the engine which they would replace it for.
 

Latest posts

Top