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

So Mazda's not the only one to have problems with oil pressure controlled HLAs. Here's an interesting article about Hemis nine years later. Many differences, and nothing definitive, but the similarities are striking. Time will tell.
 
So Mazda's not the only one to have problems with oil pressure controlled HLAs. Here's an interesting article about Hemis nine years later. Many differences, and nothing definitive, but the similarities are striking. Time will tell.
WOW!!!!

Interesting that some 3rd party engineers say the issue is due to a lack of lubrication, and that CD is not a likely culprit (judged solely by examining the failed parts.) It would be interesting to see which cylinders experienced failure on these vehicles just to test that theory.

Stinks all the way around. No matter how many miles you get out of them (and cars certainly last a lot longer than when I was younger), it's not like buying a new pair of shoes.
 
Just by way of information, I have the turbo version of the 2.5L, which does not have cylinder deactivation. That engine is in the Reserve and the Signature trims. So my experience is strictly second-hand from what I read here and elsewhere.

But all's been quite since the updates. And as you said, you have 5 years of coverage on Mazda's dime.

Wait, am I understanding right? There's an ECU update for the Turbo version too?
 
I'm wondering if my local dealers have the PCM programmers on hand or have to get them from Mazda. I haven't had this recall performed since I rather wait at the dealer instead of having the dealer's staff picking up my car. This COVID-19 crap is a PITA as far as getting service. My car has just shy of 6k miles, and due to the highway driving I do to run the car after being shutin the house all week, it's giving me the best average mileage (close to 34 mpg) ever! I'm probably not taking my car back to the selling dealer since we have had bad warranty experiences from them for our other Mazda.
 
I'm wondering if my local dealers have the PCM programmers on hand or have to get them from Mazda. I haven't had this recall performed since I rather wait at the dealer instead of having the dealer's staff picking up my car. This C-19 crap is a PITA as far as getting service. My car has just shy of 6k miles, and due to the highway driving I do to run the car after being shutin the house all week, it's giving me the best average mileage (close to 34 mpg) ever! I'm probably not taking my car back to the selling dealer since we have had bad warranty experiences from them for our other Mazda.
Call your dealer.

I went to mine (Charlottesville) for them to check out an issue when all the Virus controls had been put in place (the Customer Lounge was roped off.) I stood in the showroom until the mechanic finished. They were happy to take me in, since their entire schedule was open. They told me they were trying to keep their mechanics busy. Things may be different now/where you are.

At this point, I cannot imagine that there's a dealer who does not have the update.
 
Software fix... from my reading here, it sounds like the pressure must be above a certain level to prevent the mechanical failure for cylinder deactivation. I know that parts wear, clearances widen and pressure drops with wear and tear on an engine. 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? Mazda? Mazda?
 
Software fix... from my reading here, it sounds like the pressure must be above a certain level to prevent the mechanical failure for cylinder deactivation. I know that parts wear, clearances widen and pressure drops with wear and tear on an engine. 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? Mazda? Mazda?

Reach out to Mazda directly by writing to them...not here on forums as they likely don’t read owner forums. You can relay your concerns through the dealer and that’ll ensure the message is passed on. If you go thru the proper channels you’re likely to get a better, more accurate and technical response than from forums
 
Reach out to Mazda directly by writing to them...not here on forums as they likely don’t read owner forums. You can relay your concerns through the dealer and that’ll ensure the message is passed on. If you go thru the proper channels you’re likely to get a better, more accurate and technical response than from forums

Echoing tekz. Reach out to Mazda directly. An online forum comprised primarily of Mazda owners will not have the specific technical information or resources to obtain said information, but Mazda's head office may be able to help.
 
Software fix... from my reading here, it sounds like the pressure must be above a certain level to prevent the mechanical failure for cylinder deactivation. I know that parts wear, clearances widen and pressure drops with wear and tear on an engine. 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? Mazda? Mazda?
Your concern is exactly what I have, in addition to the bad reputation historically by cylinder deactivation. That’s why I personally gave up the plan of getting a 2018 CX-5 once I found Mazda suddenly added the cylinder deactivation feature for 2018 MY.

I myself wouldn’t be interested to get any vehicles featuring cylinder deactivation as I plan to keep my vehicles for as long as I can. Until Mazda changed its CD design with some physical fail-safe hardware to prevent the rocker arm falling, this software fix simply is a temporary patch job for the problem at the best!
 
Gentlemen,

Please stop poking up this issue.

Subject has ben dealt with by Mazda.... since many months no issues anymore.
 
Reach out to Mazda directly by writing to them...not here on forums as they likely don’t read owner forums. You can relay your concerns through the dealer and that’ll ensure the message is passed on. If you go thru the proper channels you’re likely to get a better, more accurate and technical response than from forums
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. Good luck to get more specific details about this issue from Mazda North American Operations, not to mention from any Mazda dealerships.

I personally have benefited by this forum for my CX-5, from other’s personal experience、personal knowledge、and TSBs, but almost never from Mazda dealers or MNAO!

Remember MNAO forced our forum to remove TSB thread out of the top list, now it’s hard to find and has never got updated like in the old days! Those TSBs made me saved thousands as I used those TSBs to fix several hidden problems right before my new car warranty ran out.
 
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Gentlemen,

Please stop poking up this issue.

Subject has ben dealt with by Mazda.... since many months no issues anymore.
So you’re saying a new member went through this long thread with 752 posts, but can’t post a question about the issue, and we can’t answer or comment the question he has?
 
So you’re saying a new member went through this long thread with 752 posts, but can’t post a question about the issue, and we can’t answer or comment the question he has?

His question is not one that we can answer, thus the recommendation to contact Mazda directly. As mentioned, they would have access to more information than we do. The problem is getting them to supply the information. Either way, you can't get the info without asking for it from the proper source.

Your experience is your experience, and it is of course worth taking into account. But other's experiences may vary.
 
His question is not one that we can answer, thus the recommendation to contact Mazda directly. As mentioned, they would have access to more information than we do. The problem is getting them to supply the information. Either way, you can't get the info without asking for it from the proper source.

Your experience is your experience, and it is of course worth taking into account. But other's experiences may vary.
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.
 
If you re-read the original post by OP GoHawks, 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.

Irrelevant to the question at hand. "Then" is not "now". In the beginning, there was an issue that nobody knew much about. Since then we have watched Mazda diagnose the issue, trace it back to the source, develop a fix, and roll out the recall. As of today, the software update appears to have worked. The question is how long this fix will work/is it just a temporary band-aid fix. Everyone has their own opinion on this, but as has been stated, you will not get a decent answer from a group of Mazda owners on an online forum. We are not privy to the kind of technical info TotalMazda1 is looking for. Go to the source - even if it is like trying to get blood from a stone. The opinions provided here can be taken as educated guesses at best.

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.

Again, your experience is your experience, and it is of course worth taking into account. But other's experiences may vary.
 
I have a 3 legged (cancer took one) dog that can run around the yard as if she were still on all four!
 
The design of most oil pump pressure systems includes a spring loaded maximum pressure release valve that dumps oil when the desired pressure is produced by the pump. This is necessary while the engine and pump are new with close tolerances and the oil is cold with high viscosity so that the maximum pressure is not exceeded causing damage to the pump and other bearings. As the engine and pump wear and the oil heats the pressure release valve closes to maintain the desired pressure so that an older engine will still have the needed oil pressure so I think you are safe from wear. Newer designs may have a variable displacement pump which changes the output of the pump by responding to the needed pressure thus saving energy by not pumping oil at high pressure and it being dumped. I think the Mazda design has a variable pump and actually has two levels of pressure for the engine depending on the power demand requested by the throttle. I do not think wear is an issue for oil pressure.
 
Of course the guy is asking a rhetorical question when he wants to know what oil pressure is gonna be at 200,000 miles in his car relative to that required by CD.
 
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