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

Kaps

Contributor
:
CX-5 Touring 2016.5
Hello all,

Long time member, but haven't posted in years. My wife and I have been looking to replace her 17 Toyota 4Runner with a smaller more fuel efficient car, and have decided we really like the CX-5. We went to a local dealer over the past weekend,a nd brokered a deal on a lease of a 19 Touring with preferred package in Jet Black Mica.

However we have not finalized the deal. Yesterday while at a gas station in my work van a woman pulled up to refuel in her CX-5. I asked her how she liked it. She said she loved it, but it hasn't been without troubles. She said hers had a problem with losing power, and that Mazda replaced her engine due to a rocker arm falling off. I thought that sounded fishy, but decided to do some digging on it. I found this thread. It is a little worrisome that we might be signing up for a lease on this car knowing that Mazda thinks they have it fixed with the computer re-flash, but I'm not convinced. Should I be worried? Should I not lease this car? I know it has a warranty, but I don't want to have to deal with issues, and I sure don;t want my wife to be driving this and run into a dangerous situation with loss of power, and limp mode unexpectedly.
All new drivetrains have trouble - Yota 8 spd is getting hammered on their forums for being crude, 1.5T Hondas having their issues. So you are taking a big risk - the issue I have with CD is there is no real gain unless you are driving 30-45 mph with little or no load. Think of flat roads with 30 mph limit. If this is a lot of your commute you can hammer out a great deal of mpg - even then it is not worth more than a few hundred bucks over the life of the vehicle. With Yota and Honda there are bigger benefits. Mazda is just milking a drivetrain that was at the peak in 2013/14 and 15. Got equaled in 16 and surpassed after that. My suggestion is look at the Turbo if you want to or hammer down your deal by a grand or two more - it is possible. I own a Mazda and my second car will be replaced in 2 / 3 years. My only Mazda options are 17 CX5 or 17 Mzd 6 without CD. So I am definitely out of CD goop just because its not worth it.
 

Mazdax605

Masshole
:
79 RX-7 GS,74 REPU,77 RX-3 SP
Is anyone convinced the CD issue is resolved by Mazda, and the re-flash of the ECU? The CX-5 turbo doesn't have CD, correct?
 
:
2019 CX-5 Signature Soul Red Crystal Metallic
Hello all,

Long time member, but haven't posted in years. My wife and I have been looking to replace her 17 Toyota 4Runner with a smaller more fuel efficient car, and have decided we really like the CX-5. We went to a local dealer over the past weekend,a nd brokered a deal on a lease of a 19 Touring with preferred package in Jet Black Mica.

However we have not finalized the deal. Yesterday while at a gas station in my work van a woman pulled up to refuel in her CX-5. I asked her how she liked it. She said she loved it, but it hasn't been without troubles. She said hers had a problem with losing power, and that Mazda replaced her engine due to a rocker arm falling off. I thought that sounded fishy, but decided to do some digging on it. I found this thread. It is a little worrisome that we might be signing up for a lease on this car knowing that Mazda thinks they have it fixed with the computer re-flash, but I'm not convinced. Should I be worried? Should I not lease this car? I know it has a warranty, but I don't want to have to deal with issues, and I sure don;t want my wife to be driving this and run into a dangerous situation with loss of power, and limp mode unexpectedly.
If you can afford the extra couple grand, get the GT REserve or the Signature as they have the Turbo - the Turbo has no Cylinder Deactivation in it.
 
:
2019 Mazda CX-5 GT AWD; 2017 Nissan Murano SL AWD + Tech
Hello all,

Long time member, but haven't posted in years. My wife and I have been looking to replace her 17 Toyota 4Runner with a smaller more fuel efficient car, and have decided we really like the CX-5. We went to a local dealer over the past weekend,a nd brokered a deal on a lease of a 19 Touring with preferred package in Jet Black Mica.

However we have not finalized the deal. Yesterday while at a gas station in my work van a woman pulled up to refuel in her CX-5. I asked her how she liked it. She said she loved it, but it hasn't been without troubles. She said hers had a problem with losing power, and that Mazda replaced her engine due to a rocker arm falling off. I thought that sounded fishy, but decided to do some digging on it. I found this thread. It is a little worrisome that we might be signing up for a lease on this car knowing that Mazda thinks they have it fixed with the computer re-flash, but I'm not convinced. Should I be worried? Should I not lease this car? I know it has a warranty, but I don't want to have to deal with issues, and I sure don;t want my wife to be driving this and run into a dangerous situation with loss of power, and limp mode unexpectedly.
It's a matter of how one looks at it. Personally, when I buy a car, I research the model's reliability to death. With CX-5, I'm confident enough to have recently bought a used '19 GT AWD with 15K miles (former rental, mind you) knowing that it has a mild CD compared to other more complex designs. At the same time, I'm normally against owning a turbo, CD, or any other ticking time bomb. Reading this thread worries me just a tiny bit, but I don't regret my purchase at all.
If I leased it, I wouldn't even care about this issue. I believe now that the recall is published, Mazda cannot sell a new vehicle without completing it. I think for those CX-5s already on the road with the recall complete, while there's a slight chance there may be some residual damage that the recall won't address (will likely reveal itself later), the loss of power and limp mode is no longer a threat.
 
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Mazdax605

Masshole
:
79 RX-7 GS,74 REPU,77 RX-3 SP
It's a matter of how one looks at it. Personally, when I buy a car, I research the model's reliability to death. With CX-5, I'm confident enough to have recently bought a used '19 GT AWD with 15K miles (former rental, mind you) knowing that it has a mild CD compared to other more complex designs. At the same time, I'm normally against owning a turbo, CD, or any other ticking time bomb. Reading this thread worries me just a tiny bit, but I don't regret my purchase at all.
If I leased it, I wouldn't even care about this issue. I believe now that the recall is published, Mazda cannot sell a new vehicle without completing it. I think for those CX-5s already on the road with the recall complete, while there's a slight chance there may be some residual damage that the recall won't address (will likely reveal itself later), the loss of power and limp mode is no longer a threat.
I thought I had done my research pretty well, but I hadn't heard of the CD issues until I ran into an owner yesterday at the filling station who told me about her engine being replaced. The idea of getting this on a lease is to make it more affordable for us right now compared to the 4Runner. This also let's us walk away in three years but a lot can happen in that time. I worry about the car going into limp mode with my wife and kids in the car or my wife a niece who she will be nannying for starting next month. I want/need reliable.
 
Hello!
I am cx-5 2019 owner in Europe. I learned about CD system only after information about last recall. I have already passed PCM update procedure, but want to understand more about CD system now. Is it possible to inspect modes when this system is working? I have OBDII adapter and Forscan software. Is it possible to monitor some CD related sensors?
Thanks!
 
:
CX5 GT +pp 2018
Thwre are no parameters for CD monitoring as far as I know.
You can theoretically monitor fuel pressure. It seems to drop in CD mode vs normal operations but you have to get a good understanding of normal ranges first and gather historical values.
Then you can (kind of) see when it drops for prolonged periods.
Its too much efforts so not really worth it to monitor CD that way.
Just enjoy your car.
 

Avoidin Deer

Zoom Zoom, baby
Contributor
:
Central Virginia
:
2019 CX-5 Reserve
I thought I had done my research pretty well, but I hadn't heard of the CD issues until I ran into an owner yesterday at the filling station who told me about her engine being replaced. The idea of getting this on a lease is to make it more affordable for us right now compared to the 4Runner. This also let's us walk away in three years but a lot can happen in that time. I worry about the car going into limp mode with my wife and kids in the car or my wife a niece who she will be nannying for starting next month. I want/need reliable.
Out of curiosity...did you even know the cX-5 had introduced CD in 2018 before you bought your car? I never came across anything that even referenced it.
 
:
2018 CX5 GT, Metallic Machine Gray and 2018 MX-5 RF GT, Soul Red
Out of curiosity...did you even know the cX-5 had introduced CD in 2018 before you bought your car? I never came across anything that even referenced it.
When I purchased my 2018 CX5 the salesman used the CD feature as a sales pitch for better mileage. It was also included in the Canadian version of Mazda CX5 sales brochure that I picked up on my first test drive and after purchasing the vehicle I noticed it was also listed on the "window sticker".

Wade
 

Mazdax605

Masshole
:
79 RX-7 GS,74 REPU,77 RX-3 SP
Out of curiosity...did you even know the cX-5 had introduced CD in 2018 before you bought your car? I never came across anything that even referenced it.
We haven't even bought the CX5 yet. We were all set to buy one and might still. I was at a filling station and ran into a woman who had one and I asked her how she liked it. She said she loved it, but has had issues, most notably the engine being replaced due to a rocker arm problem. She mentioned that Mazda has/had a recall on it. I went home that evening and did some research, finding this thread and now I'm worried about it.
 

Avoidin Deer

Zoom Zoom, baby
Contributor
:
Central Virginia
:
2019 CX-5 Reserve
When I purchased my 2018 CX5 the salesman used the CD feature as a sales pitch for better mileage. It was also included in the Canadian version of Mazda CX5 sales brochure that I picked up on my first test drive and after purchasing the vehicle I noticed it was also listed on the "window sticker".

Wade
When you mentioned the brochure, I decided to go back to the "Build Your Own" portion of Mazda's website. The first entry in Read More section of the 2018 CX-5 Grand Touring says:
187-hp, SKYACTIV-G4 2.5L DOHC 16-valve 4-cylinder engine with Cylinder Deactivation
All those times I was in that area and glossed right over that.
 
:
2018 CX-5 Sport
If you are going to lease it for a few years, I wouldn't let it change your mind. Or get the turbo charged model. I plan to keep my car 10 years or more. When I bought mine, I picked Mazda designed CD over turbo of any make only because I know turbos work engines hard and turbos themselves work extremely hard and can start leaking and they are expensive. I feel fine with the Mazda fix, but if I heard about this recall before buying, I would still be driving my old car until some manufacturer made a no frills engine or that CD was found to be rock solid years from now. That being said I do love my car. I (and you guys) happen to be the guinea pigs for CD.
 

Mazdax605

Masshole
:
79 RX-7 GS,74 REPU,77 RX-3 SP
If you are going to lease it for a few years, I wouldn't let it change your mind. Or get the turbo charged model. I plan to keep my car 10 years or more. When I bought mine, I picked Mazda designed CD over turbo of any make only because I know turbos work engines hard and turbos themselves work extremely hard and can start leaking and they are expensive. I feel fine with the Mazda fix, but if I heard about this recall before buying, I would still be driving my old car until some manufacturer made a no frills engine or that CD was found to be rock solid years from now. That being said I do love my car. I (and you guys) happen to be the guinea pigs for CD.
CD isn't new. GM has been using what they call DoD (displacement on demand) for years and it's not good at all. As a matter of fact a lot of manufacturers are using or have used CD, and most of them are either not worth the hassle, or downright terrible. I just worry that Mazdas system is possibly terrible on what is already a pretty new engine design.
 
Thwre are no parameters for CD monitoring as far as I know.
You can theoretically monitor fuel pressure. It seems to drop in CD mode vs normal operations but you have to get a good understanding of normal ranges first and gather historical values.
Then you can (kind of) see when it drops for prolonged periods.
Its too much efforts so not really worth it to monitor CD that way.
Just enjoy your car.
I saw on this theme some pictures with graphical indication of CD system (new Mazda 3,6?). So, probably some PIDs can be interpreted in that way.

The other question: how the car with non functional engine part (1 of 2 valves on 1 on 4 cylinders) can be operated normally in most of daily usage? And even more, there are no known software diagnostics issues which can reveal a hardware problem (again, Forscan, PIDs).
 

Avoidin Deer

Zoom Zoom, baby
Contributor
:
Central Virginia
:
2019 CX-5 Reserve
I saw on this theme some pictures with graphical indication of CD system (new Mazda 3,6?). So, probably some PIDs can be interpreted in that way.

The other question: how the car with non functional engine part (1 of 2 valves on 1 on 4 cylinders) can be operated normally in most of daily usage? And even more, there are no known software diagnostics issues which can reveal a hardware problem (again, Forscan, PIDs).
As others have pointed out, CD has been around for a while. I don't now when it was first implemented, but I first encountered it maybe 10 years ago on a friend's truck, which was not new at the time. It is not operating "in most of daily usage." There's a narrow range of conditions within which it is engaged. That's why folks are saying it barely improves mileage...CD rarely kicks in.

I don't believe the guy was asking diagnostics to tell when there's a hardware problem [with the rocker], he wanted to know when the car's software engaged/disengaged the CD function, since you can't really tell when it does just by feel. That information is available in the computer...the problem is accessing it.

All of this stuff (like Direct Inject and its attendant oil dilution issues) is picking at the fringes solely to meet government's fuel efficiency standards.
 
As others have pointed out, CD has been around for a while. I don't now when it was first implemented, but I first encountered it maybe 10 years ago on a friend's truck, which was not new at the time. It is not operating "in most of daily usage." There's a narrow range of conditions within which it is engaged. That's why folks are saying it barely improves mileage...CD rarely kicks in.
The only thing that doubt me in context of CD failures is the absence of software ability to detect whether all parts of engine works as they should work. I try to estimate probability of engine damage. How often CD was triggered? What concrete conditions did increase probability of arm falling of? And finally, what probability that rocker arm is on the correct place?
 
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You cannot determine the probability of such a fault. It is uncertain what it is caused (not so sure that is caused by software bug - my opinion), not enough cases, etc. The best you can do is update the PCM, drive and monitor.

I will try soon to confirm the method of checking the arm using an endoscopic camera and post information here on the forum.

I already have a camera with a rigid cable, maybe I will start doing it today.
 

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