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

For the CD concern. I know one guy on the forum got his fixed and he is in NJ. I don't get why mine gets that message. I called the dealership a week or two ago and they said they didn't have the part yet and they would call me when they got the part in. I have delayed calling them because I want them to fix a few before me so they get some practice doing it (help)

Gotcha. That's a smart tactic.

I hope you (and everyone else) get it remedied soon and can make this a distant memory...
 
$800 to visually inspect

Jeez...that's like a new set of tires!!

Also keep in mind that if you do go forward and want it popped to visually inspect, you will need to have a new valve cover gasket to replace the old one to make sure it creates a good seal and dont start a new set of issues.
 
I saw mentioned earlier in the thread talk of running rich. I'm assuming this is because the rocker arm that fell is over an intake valve? Is this always the case or is it possible for a rocker to fall off an exhaust valve? Do exhaust valves have rocker arms? During CD, I doubt the rockers would change their pivot point and only stop the movement of the intake valves while the exhaust valves keep moving. I'm not an expert so please let me know if anything I say sounds off.

Let's assume it's only a rocker over an intake valve that can fall off. Wouldn't an OBDII scanner tell you that one of your cylinders is running rich immediately after some spirited driving (if not a stored code, then atleast a pending code that doesn't trigger CEL)? I'm thinking of doing this after I get the PCM update and wanted to get some thoughts from you guys if this would just be a waste of time. My logic is that if the rocker arm is off, the intake valve is always shut no matter how hard I accelerate. This should throw atleast one pending code while accelerating hard. If a rocker is off but no code thrown while engine is running at its limited peak, then it's either not much of a concern anymore after the PCM update or Mazda disabled the throwing of relevant codes for those cylinders. I would like to doubt that it's the latter since thats very shady and has the potential to ruin their company reputation.

Last question, is there a schematic I can refer to determine which valves are intake and which are exhaust? It's not clear which is which when looking at just the photos posted here. Thanks for those amazing high quality photos btw!
 
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I saw mentioned earlier in the thread talk of running rich. I'm assuming this is because the rocker arm that fell is over an intake valve? Is this always the case or is it possible for a rocker to fall off an exhaust valve? Do exhaust valves have rocker arms? During CD, I doubt the rockers would change their pivot point and only stop the movement of the intake valves while the exhaust valves keep moving. I'm not an expert so please let me know if anything I say sounds off.

Let's assume it's only a rocker over an intake valve that can fall off. Wouldn't an OBDII scanner tell you that one of your cylinders is running rich immediately after some spirited driving (if not a stored code, then atleast a pending code that doesn't trigger CEL)? I'm thinking of doing this after I get the PCM update and wanted to get some thoughts from you guys if this would just be a waste of time. My logic is that if the rocker arm is off, the intake valve is always shut no matter how hard I accelerate. This should throw atleast one pending code while accelerating hard. If a rocker is off but no code thrown while engine is running at its limited peak, then it's either not much of a concern anymore after the PCM update or Mazda disabled the throwing of relevant codes for those cylinders. I would like to doubt that it's the latter since thats very shady and has the potential to ruin their company reputation.

Last question, is there a schematic I can refer to determine which valves are intake and which are exhaust? It's not clear which is which when looking at just the photos posted here. Thanks for those amazing high quality photos btw!
Theres a cutaway drawing and a short video showing the valve train on SkyActiv-G with cylinder deactivation from exhaust side by Inside Mazda:

MAZDAS NEW CYLINDER-DEACTIVATION OFFERS IMPROVED FUEL-EFFICIENCY WITHOUT SACRIFICING DRIVING PERFORMANCE

I also took some screenshots out of the video in post #33 earlier in this thread.

No, cylinder deactivation will shut off both intake and exhaust valves. Thus it requires more energy to compress and expand the air of disabled cylinders in a mostly sealed environment. This means the system isnt as efficient.

So far we have only seen the very last of intake rocker arm of cylinder #4 fallen. Apparently theres a pocket big enough to let the rocker arm fall. Others seem to be having no space to fall, but once a rocker arm is too loose to be out of position, the wobbling rocker arm definitely will hit some valve train components and damage them even thought the rocker arm has no place to fall.
 
Noticed the recall when looking online at used 2018 CX-5s, I bought mine last year. I didnt think too much about CD at the time so hopefully Mazda knows what theyre doing. This is my first Mazda, almost bought a 3 in 2016 and almost bought one instead of my CX-5 last year, and the CX-5 was considerably more expensive. I love the CX-5 but feel a little iffy on long term reliability. So far, no issues. Took my car to redline twice today on the freeway and its been as smooth as its always been. I cant find the combination of features and driving quality like Mazda in what Im willing to pay so I was even thinking about a 2018 3 if I can find a good one. My CX-5 is paid off so I have a little more wiggle room if this CD rocker arm turns out to be a longer term issue. Im at 12,900 miles now on my CX-5 Touring AWD. Thank you to all of those who contributed to this thread, it was a good read!
 
$450 to visually inspect the Rocker Arm

I had the Recall done today and I want to share my experience.

My dealership quoted me $450 to open up the valve cover for the visual inspection of the rocker arm. The person that took care of me strongly against this idea as it is not part of the recall, although the labor cost will be on me. He reminded me that my car (19 CX-5 Touring) only has 3300 miles/5 months old and therefore has a lot of miles/time left until the warranty is up. If there is a case where the warranty is about to expire, then he is more supportive of the rocker arm inspection. He has a point there. But he also said that he will do whatever I wish. The $450 is more than I was willing to pay and there is also a risk in disassembly/reassembly of the valve cover(eg. sloppy tech). So I decided to only do the PCM update - part of the reason was that while on my way to the dealership, I put my car into Sport mode and rev it up to 5K+ several times(could not hold it there longer than 1 second because the car would automatically shifted; I know, I know...I should have done it in manual mode). Similarity, I pretended to pass a car many times by going hard on the accelerator - no limp mode.

Before the service guy handed me the key back, he kindly told me that the tech that did the PCM update wanted to remind me that the warranty in the areas of my concern is a 5yr/60K miles, not the 3yr/36K because the rocker arm/cylinder is part of the powertrain components. All this time I thought the rocker arm related warranty is a 3yr/36k. (Forgive my lack of awareness and for those that are like me, now you are aware). You can also double check what is covered under powertrain warranty(5yr/60k) in your Warranty booklet that came with the car. Another piece of info - Honda recently extended the warranty to 6yr/unlimited miles on the powertrain for owners of Honda CRV with 1.5L turbo engine due to oil dilution and rocker arm issue....you read that right, rocker arm assembly issue. So it is a powertrain related component. And yes, my Trip (A&B) got reset to 0 after the update.
 
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I had the recall done a couple weeks ago along with current tsb android auto update. Our mpg has dropped 2 - 3 mpg since. The recall firmware must have changed fuel mixture also.
 
I had the recall done a couple weeks ago along with current tsb android auto update. Our mpg has dropped 2 - 3 mpg since. The recall firmware must have changed fuel mixture also.

The plot thickens....
 
I had the recall done a couple weeks ago along with current tsb android auto update. Our mpg has dropped 2 - 3 mpg since. The recall firmware must have changed fuel mixture also.

Unless "Cylinder Deactivation" is being completely deleted and Mazda is not saying anything.

Let's face it, vehicle manufacturers have done much worse in recent times. Does VW sound familiar?. :)

It's all about the bottom line, even if a few lives have to be lost in the process.

There is no reason to trust big business. They are not our "Friends".
 
Unless "Cylinder Deactivation" is being completely deleted and Mazda is not saying anything.

Let's face it, vehicle manufacturers have done much worse in recent times. Does VW sound familiar?. :)

It's all about the bottom line, even if a few lives have to be lost in the process.

There is no reason to trust big business. They are not our "Friends".

All true.

But, if Mazda has decided that they have to disable CD, then presumably they'll be doing it for new cars coming from the factory. They'd have to stop advertising the cars as having CD. No sign of that.

Meanwhile, Mazda never claimed 2-3 mpg gain with CD, so maybe something else is going on with OFSilverbullet's car.
 
All true.

But, if Mazda has decided that they have to disable CD, then presumably they'll be doing it for new cars coming from the factory. They'd have to stop advertising the cars as having CD. No sign of that.

Meanwhile, Mazda never claimed 2-3 mpg gain with CD, so maybe something else is going on with OFSilverbullet's car.

I doubt CD is contributing much of anything to fuel economy. It could be a coincidence of timing with the recall work, but CD isn't even on unless you are sustained speeds within 25-50 mph.
 
All true.

But, if Mazda has decided that they have to disable CD, then presumably they'll be doing it for new cars coming from the factory. They'd have to stop advertising the cars as having CD. No sign of that.

Meanwhile, Mazda never claimed 2-3 mpg gain with CD, so maybe something else is going on with OFSilverbullet's car.

They may have a mechanical fix to current production.
 
CX-5 is 10 months old with 3,000 miles. I have been keeping an eye on the mpg since day one. Went from 24.5 - 26.5 in same city driving weekly to 22-23.5 mpg. Service mgr. said to skeep record for a few weeks more. If it stays down he will check with tech line about it.
 
I'm having the same issue since the recall. Before it, I was averaging 21-22 mpg in mainly city traffic driving. Since the recall, while driving the same routes, my mpg average is now down to 19. Also, when I filled up my gas tank before the recall, the gauge would say I had 282 miles left on a full tank. Now, it says I have 262 left on a full tank. Something definitely changed with the recall.
 
Yes, that is correct and your point is.............;)

I believe that fact has been covered already in this thread to a certain degree.

Trans7270 post indicated he had a 19 CX-5 T and was worried about the recall so I guess he has not read all the post...
 
Trans7270 post indicated he had a 19 CX-5 T and was worried about the recall so I guess he has not read all the post...

I believe he is referring to his 19 CX-5 T (Touring), which does not have a turbo.
 
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