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

My theory is that the lifter was bad and fell off right away. The reason I think this is when I zoomed in on the picture I see what appears to be the number 15 on the cam lobe which I circled. This would have been worn away and the lobe shiny like all the other ones are. I couldn't see any numbers on any other lobes.

Cam.jpg
 
This is the lobe next to the one with the variable lifter. It appears to have a lot more wear and even seems to have a scratch. In conclusion, if you have an affected car, your lifter is probably already fallen off and you just don't know it. This is purely speculation on my part though.

Cam2.jpg
 
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I went through the same thing.

Researching cars is like reading the negative reviews on Amazon. You sometimes walk away feeling like your best option is to do nothing. Eventually you just hold your nose and jump in, hoping for the best (helluva way to spend ten$ of thousand$).

I dodged the Honda oil dilution issue because my brother (a mechanic) warned me against new engines, so I did research I would not have otherwise done (I was relying on the CR-V popularity.)

I dodged the Mazda CD issue only because life issues got in the way when car shopping in the fall of 2018. When I picked up again in February, the turbo had been released. But now there are folks talking about the turbo occasionally not working in certain weather conditions. Like you, I read a lot on these sites and independent reviews, and did not see any major negative issues (except the SCRM paint, which is easily avoided by making a different color choice).

This is not like buying a $50 drill that does not perform properly. You get much better customer service when spending way less money. And even if you have to eat it, it's only $50.

A car is not so easy to get out from under...and it ain't cheap. It's this lack of sufficient relief that spikes the angst.

Yep, Toyota recalling the 2019 Ravs with trans problems, Subara with valve train problems...it's like the late 70s early 80s all over again, car manufacturers putting out crap.
 
Yep, Toyota recalling the 2019 Ravs with trans problems, Subara with valve train problems...it's like the late 70s early 80s all over again, car manufacturers putting out crap.

Yes, and charging us a small fortune for that crap.
 
Yep, Toyota recalling the 2019 Ravs with trans problems, Subara with valve train problems...it's like the late 70s early 80s all over again, car manufacturers putting out crap.
Wait, I did see Toyota has issued a recall for 3,400 of its 2019 Corolla Hatchback models in the U.S. due to the torque converter problem in its CVT which could fail and result in the loss of power.

So what's the problem on 2019 RAV4 with its 8-speed transmission?
 
Wait, I did see Toyota has issued a recall for 3,400 of its 2019 Corolla Hatchback models in the U.S. due to the torque converter problem in its CVT which could fail and result in the loss of power.

So what's the problem on 2019 RAV4 with its 8-speed transmission?

I can't find the place where I saw the RAV 4 trans being recalled, maybe a mistake, discount that for now. Anyway, numerous problems and complaints with the 2019 RAV4 transmission with rough shifting.

https://www.toyotanation.com/forum/...19/1647982-clearinghouse-issues-new-rav4.html
 
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My theory is that the lifter was bad and fell off right away. The reason I think this is when I zoomed in on the picture I see what appears to be the number 15 on the cam lobe which I circled. This would have been worn away and the lobe shiny like all the other ones are. I couldn't see any numbers on any other lobes.

Cam.jpg

I don't think I've ever seen a cam lobe with anything imprinted or just printed on them. All have been smooth.
Not to say that it's never been done, but the finish on the cam lobe surface is almost as critical as the bearing surfaces.
 
I don't think I've ever seen a cam lobe with anything imprinted or just printed on them. All have been smooth.
Not to say that it's never been done, but the finish on the cam lobe surface is almost as critical as the bearing surfaces.

I don't think it is as critical with roller cam followers as it was with the old sliders...
 
The voucher is expressly to cover the work of removing the valve cover. It was never meant to be for any other purpose. I'm well aware that someone is covering the cost and that the dealership isn't going to do the work for free.

My point with the comment "this probably isn't the way things are supposed to work" was simply voicing frustration over the fact that if there is no code or no noise then there is apparently no problem. This is in spite of the fact that in this case I have documentation that there was an previous issue specific to my car and an associated TSB that outlined instructions to inspect the car that wasn't followed the first time around. I've read on this thread that people can't believe that the dealership doesn't know about certain TSB's. To a certain extent that may be true that techs need to be informed but in reality dealerships are servicing many Mazda models from across multiple years. To expect the service team to know each and everyone offhand for all makes/models/years is unrealistic but I would expect that they at least put a little more effort into investigating the problems that customers bring in.

The bottom line is that the dealership was in a no win situation where Mazda wasn't going to pay for the work based on their corporate technician's assessment and I wasn't willing to pay out of pocket on something I felt should be covered under the powertrain warranty. Mazda Customer Service was quick to provide a solution in the form of a voucher after I raised the issue as a safety concern and explained the situation. Kudos to them.


Today's update is that the dealer pulled the valve cover and found there is an issue with the cylinder #4 "lifter arm". I asked for clarification on rocker arm vs lifter arm and it sounded to be the same thing. Mazda Corporate has asked for pictures and videos from the dealership and will provide input to the dealership on next steps. Stay tuned.

Are they going to replace the engine? I am curious about the follow through.
 
Here's the latest update I have.

- A new engine has been authorized by Mazda Corporate.
- According to the technician this is a new engine, not a refurbished one
- I pressed the service guy to call the Mazda Field Service Engineer to find out why they are confident this engine won't fail. They ultimately came back to the same answer they gave to Go Hawks. The PCM update is sufficient to keep oil pressure to keep the rocker arm from falling off.
- Should take about 1.5-2 Weeks for engine delivery and installation


I'm currently in a 2019 CX5 Touring courtesy of the dealership and have put on about 1000 miles since I got it. I have been trying all sorts of different combinations to see if this is repeatable with this particular car. I've gone to redline from a stop, from a constant 45mph to redline, from 60mph to redline and downshifting to get to redline. I haven't had any issues and the loaner drives just fine.

If its gnawing at you to know if you're affected, here are some of my observations and thoughts regarding my case.

1. I observed noticeable slowness while merging into and out of traffic on the freeway. I would see a gap i would want to merge into but the car would be too sluggish to react when I gave it gas and the gap would close and I'd miss the merge. I attributed this to the fact that I was used to driving an Acura RSX and went from zipping around in traffic to an SUV. I didn't have a baseline comparison. The loaner CX5 is much easier to maneuver in traffic and I can tell a difference. Take note if you feel like your CX5 is unusually sluggish.

2. City Gas Mileage. My city gas mileage was really poor 17-20mpg. I thought my aggressive driving style led to the terribleness in city mpg but the rocker arm falling off may could have been more of a contributor. On the 19' touring my city gas mileage is much better (~25mpg). The 19' is a FWD compared to my AWD but 17-20 was still low in my opinion. My highway mileage was actually not bad and actually stayed in the 29-31 range.

3. Noise. when slowing moving through a parking lot, or at a stoplight I would sometimes hear inconsistencies in engine idle (possible rattle?). Nothing ever enough for me to complain to the dealership about bc it was inconsistent and super faint. I am speculating that was due to the rocker arm rattling around. I haven't heard that on the 19' I'm driving.

If you're have the combination of issues I've noted above then you may want to check with your dealership to discuss the symptoms you are seeing. I would avoid allowing them to update the PCM because if you're rocker arm has fallen off that will only mask the problem because even with the rocker arm off, the flash does "fix" the issue.

I have an open case with Mazda Customer Support Right now and I want to talk to them about having them add the affected PCM versions to the TSB. It doesn't do the service guys any good if they don't know which PCM versions are bad. They're only reactive to the codes thrown or customer complaints of low power. If it truly is a case of the wrong PCM version then its not that hard to identify if you're affected. Maybe that makes too much sense for Mazda.
 
Here's the latest update I have.

- A new engine has been authorized by Mazda Corporate.
- According to the technician this is a new engine, not a refurbished one
- I pressed the service guy to call the Mazda Field Service Engineer to find out why they are confident this engine won't fail. They ultimately came back to the same answer they gave to Go Hawks. The PCM update is sufficient to keep oil pressure to keep the rocker arm from falling off.
- Should take about 1.5-2 Weeks for engine delivery and installation


I'm currently in a 2019 CX5 Touring courtesy of the dealership and have put on about 1000 miles since I got it. I have been trying all sorts of different combinations to see if this is repeatable with this particular car. I've gone to redline from a stop, from a constant 45mph to redline, from 60mph to redline and downshifting to get to redline. I haven't had any issues and the loaner drives just fine.

If its gnawing at you to know if you're affected, here are some of my observations and thoughts regarding my case.

1. I observed noticeable slowness while merging into and out of traffic on the freeway. I would see a gap i would want to merge into but the car would be too sluggish to react when I gave it gas and the gap would close and I'd miss the merge. I attributed this to the fact that I was used to driving an Acura RSX and went from zipping around in traffic to an SUV. I didn't have a baseline comparison. The loaner CX5 is much easier to maneuver in traffic and I can tell a difference. Take note if you feel like your CX5 is unusually sluggish.

2. City Gas Mileage. My city gas mileage was really poor 17-20mpg. I thought my aggressive driving style led to the terribleness in city mpg but the rocker arm falling off may could have been more of a contributor. On the 19' touring my city gas mileage is much better (~25mpg). The 19' is a FWD compared to my AWD but 17-20 was still low in my opinion. My highway mileage was actually not bad and actually stayed in the 29-31 range.

3. Noise. when slowing moving through a parking lot, or at a stoplight I would sometimes hear inconsistencies in engine idle (possible rattle?). Nothing ever enough for me to complain to the dealership about bc it was inconsistent and super faint. I am speculating that was due to the rocker arm rattling around. I haven't heard that on the 19' I'm driving.

If you're have the combination of issues I've noted above then you may want to check with your dealership to discuss the symptoms you are seeing. I would avoid allowing them to update the PCM because if you're rocker arm has fallen off that will only mask the problem because even with the rocker arm off, the flash does "fix" the issue.

I have an open case with Mazda Customer Support Right now and I want to talk to them about having them add the affected PCM versions to the TSB. It doesn't do the service guys any good if they don't know which PCM versions are bad. They're only reactive to the codes thrown or customer complaints of low power. If it truly is a case of the wrong PCM version then its not that hard to identify if you're affected. Maybe that makes too much sense for Mazda.

Thanks! I still feel like the bad ones came from the factory already broken, maybe from the short drive that all of them get. Jjm86m did your car have those symptoms when brand new? Or did those symptoms appear later?
 
went to local mazda dealer and had a talk with lead tech there.

Surprisingly he knew about , and admitted to the CD issues .........

I said I was concerned about my rocker arm falling off, he said my 2019 has the software fix, and only affected years
were 2018........... now.........

We went and test drove another cx 5 , 2018 and it drove and had same characteristics as mine , guess I'll just
keep all this info in my overstrained brain, and drive on...........(drive)

thanks
 
went to local mazda dealer and had a talk with lead tech there.

Surprisingly he knew about , and admitted to the CD issues .........

I said I was concerned about my rocker arm falling off, he said my 2019 has the software fix, and only affected years
were 2018........... now.........

We went and test drove another cx 5 , 2018 and it drove and had same characteristics as mine , guess I'll just
keep all this info in my overstrained brain, and drive on...........(drive)

thanks

So did he put forth an opinion (direct or implied) on the effectiveness of the software fix? Did he seem to think it truly addresses the root problem, or does he believe it to be a band aid?
 
went to local mazda dealer and had a talk with lead tech there.

Surprisingly he knew about , and admitted to the CD issues .........

I said I was concerned about my rocker arm falling off, he said my 2019 has the software fix, and only affected years
were 2018
........... now.........

We went and test drove another cx 5 , 2018 and it drove and had same characteristics as mine , guess I'll just
keep all this info in my overstrained brain, and drive on...........(drive)

thanks
Based on the Service Alert Mazda submitted to NHTSA, the problem does include 2019 CX-5:

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Mazda Service Alert SA-015_19_01.jpgMazda Service Alert SA-015_19_02.jpg
 
he just said it was fixed with the 2019's .......... with that software update......

but just looking at what yrwei52 posted , looks like it's just a temp fix, just guessing..........

I wish I brought a print out of that service alert............. have one now...........and when I go back
for some other question/answers, I'll bring this printout plus any other questions ............

amazing all the info on this site............. whether 50% true or accurate......... still alot to take in.......
 
he just said it was fixed with the 2019's .......... with that software update......

but just looking at what yrwei52 posted , looks like it's just a temp fix, just guessing..........

I wish I brought a print out of that service alert............. have one now...........and when I go back
for some other question/answers, I'll bring this printout plus any other questions ............

amazing all the info on this site............. whether 50% true or accurate......... still alot to take in.......

Note the reference to SA-041/18 in the above under Repair Procedure in the event of discovered broken/dislocated rocker arms.

Here it is on the NHTSA website. It outlines the steps the mechanic/dealer is to take.
 
he just said it was fixed with the 2019's .......... with that software update......

but just looking at what yrwei52 posted , looks like it's just a temp fix, just guessing..........

I wish I brought a print out of that service alert............. have one now...........and when I go back
for some other question/answers, I'll bring this printout plus any other questions ............

amazing all the info on this site............. whether 50% true or accurate......... still alot to take in.......

The 2019's can have the issue, it is the same motor. The software update is so the check engine light won't go on. That is what they did to jjm86m's car after his went into limp mode and the lights went on. After they did the software update he no longer got a check engine light and he continued to drive the car. Then after seeing this thread he insisted that they check the valves and low and behold the rocker arm assembly was off.
I think that if you can accelerate fine and drive 80mph a few times without your car going into limp mode, your car is not one of the ones affected with the problem. I wouldn't be surprised if there was more wrong with the affected engines because the 'fix' is installing a new engine instead of replacing the rocker, which would be much cheaper to do.
 
I wouldn't be surprised if there was more wrong with the affected engines because the 'fix' is installing a new engine instead of replacing the rocker, which would be much cheaper to do.

That is the key. Of course Mazda is not forthcoming with the full story.
 
I wouldn't be surprised if there was more wrong with the affected engines because the 'fix' is installing a new engine instead of replacing the rocker, which would be much cheaper to do.
That is the key. Of course Mazda is not forthcoming with the full story.
Agreed. MyFirstMazda said it correctly that PCM software update is to not only raise the oil pressure in HLA like Mazda claimed, but also make CEL won't turn on even thought the rocker arm is laying down there based on jjm86m's experience. I believe this only masks the problem, and also indicates Mazda may not know why and how the problem happens. Yeah, if the problem can be resolved by simply raising the oil pressure, Mazda can also easily replace the fallen rocker arm back into the position and not to replace the entire engine which definitely is a lot more expensive.
 
Agreed. MyFirstMazda said it correctly that PCM software update is to not only raise the oil pressure in HLA like Mazda claimed, but also make CEL won't turn on even thought the rocker arm is laying down there based on jjm86m's experience. I believe this only masks the problem, and also indicates Mazda may not know why and how the problem happens. Yeah, if the problem can be resolved by simply raising the oil pressure, Mazda can also easily replace the fallen rocker arm back into the position and not to replace the entire engine which definitely is a lot more expensive.

So if Mazda is replacing engines without the force of government or lawyers, do you think we can infer that the number of affected vehicles is small?
 
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