Dangerous cylinder deactivation trouble on 2018 CX-5 and Mazda6 models

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.

I believe that some uncommon driving conditions was met to cause this problem. I have already updated PCM and only hope that these conditions were not met BEFORE software update...

Is it possible to access undercover of engine without it disassembling?
 
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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.

GM used cylinder deactivation on their trucks as early as 2005 I believe. They called it Displacement on Demand, or DoD. It turned a V8 into a 4 cylinder. I don't remember if it shut off one whole bank of cylinders, or if it was two on one side and two on the other. I do know it caused massive engine troubles, and there are kits made by the aftermarket to eliminate this system.
 
GM used cylinder deactivation on their trucks as early as 2005 I believe. They called it Displacement on Demand, or DoD. It turned a V8 into a 4 cylinder. I don't remember if it shut off one whole bank of cylinders, or if it was two on one side and two on the other. I do know it caused massive engine troubles, and there are kits made by the aftermarket to eliminate this system.

I didn't know that. He never mentioned any issues, but he was the kind of guy who traded in pretty frequently.

My current concern is with Direct Inject. It seems everyone has an oil dilution issue to some degree or another.
 
While we're waiting for the endoscope footage, I tried making a video of the CD action on my Mazda6:


I apologize the quality and shaking.. need better gear. In fact, I will do some more quality recordings of the exhaust sound next week :D
 
While we're waiting for the endoscope footage, I tried making a video of the CD action on my Mazda6:


I apologize the quality and shaking.. need better gear. In fact, I will do some more quality recordings of the exhaust sound next week :D

Pretty cool. I wish the CX-5 had that display. Yours goes into 2 cylinder mode a lot. I can assume when mine is in 2 cylinder mode from my speed/load but I can not tell by sound or feel.
 
I did the Oil change yesterday at 12,000 mi on cx 5 2018 GT and they check at registration and said that I was due for the CD recall and they told me it won't be long and that they had done on other customers and that no one had came back with complaints after the recall, so the oil change and the recall all together took probably about in hour, the trip computer was reset both A B trips,
So I didn't notice any significant changes if so, it may be m a little more responsive I make drove it for 70 mi hey and about 15 mi City and the mpg reads 35, the dealership note the recall was completed on the bill as follows: recall campaign 3719F
 
I will like to know if Mazda is going to offer software upgrade in other models in this case cx 5 to have the CD monitoring in the screen , if any one got this please let us know
Thanks..
 
As promised, I am posting a photos of valve seat inspection using endoscope.

As you can see, the levers on cylinder I (on the left when you stand in front of the hood) and IV (right) are in place.

left_1.jpg


right_4.jpg



My remark is that you must be very careful when carrying out such an inspection. The cheap chinese plastic endoscope is quite delicate and it is better that none of its elements remain under the valve cover. You should gently operate because you can wedge the endoscope somewhere.


The positive thing is that there is no need to pay for removing the valve cover, but remember that you do it at your own risk and you may lose your warranty.


Checking the levers with the camera is 5 minutes of work (drive)!!!

endoscope.jpg


inside_2.jpg


inside.jpg



The above photo is not my authorship. The original photo can be found on page 15 of this thread.

I marked on it how far you have to reach with the endoscope to see the right levers.


I hope you save a few bucks with this guide. (yippy)
 
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You are a brave man for doing that. I would have feared getting my camera stuck, and then having to call a tow truck to haul the car to the dealer!!! I imagine you took it very slowly, especially around the bends.

Your experiment begs the question: "Why don't the dealers do this rather than removing the valve cover?" It sure seems it would be a way less expensive option.
 
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You are a brave man for doing that. I would have feared getting my camera stuck, and then having to call a tow truck to haul the car to the dealer!!! I imagine you took it very slowly, especially around the bends.

Your experiment begs the question: "Why don't the dealers do this rather than removing the valve cover?" It sure seems it would be a way less expensive option.


I wrote a little too much. The thing is that you can handle it calmly, you just have to be careful when inserting and removing the camera. If it gets stuck, you can unlock it with gentle movements.
Now I could repeat the action many times easy.
 
I wrote a little too much. The thing is that you can handle it calmly, you just have to be careful when inserting and removing the camera. If it gets stuck, you can unlock it with gentle movements.
Now I could repeat the action many times easy.


Thanks for that info...Im coming over, how much do you want to look at mine?! 😆
 
Due to the simplicity of this procedure, Mazda could facilitate its work and check the valve levers in this way, while as a thank you I can accept the new Mazda 6 Turbo with delivery at home. (thumb)
 
I wrote a little too much. The thing is that you can handle it calmly, you just have to be careful when inserting and removing the camera. If it gets stuck, you can unlock it with gentle movements.
Now I could repeat the action many times easy.

Would you make a youtube video? It would be amazing to see what it sees as you move it inside the valve cover. Your engine is nice and clean, how often do you change your oil?
 
It will be hard with the video because I have only one phone that I just connect to the endoscopic camera. But I guarantee you manage it.

As for oil, Mazda in Europe requires an oil change in these engines every 20 000 km. This is definitely too much. I change the oil every 10 000 km, except that the first change was at 3000 km.

I use oil imported from the USA - Amsoil Signature 0W20. It has very good parameters and is widely recommended for these engines here in my country.
 
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