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

well it looks like the fix is an updated part and software update to the PCM/ECU. I'm not sure. The verbage is a little ambiguous
Actually, with the exception of the PCM control software update, what they're saying in the TSB sounds crystal clear to me.

There's nothing to indicated Mazda updated the part (engine oil solenoid). They said the solenoid is getting contaminated and is not functioning properly (sticking), as a result of the contamination, and so they're telling the tech to just replace it with a new, clean one.

Next they say in the TSB that a PCM update was done to 'eliminate the concern'. Now that part isn't totally clear to me, but it sounds like it MIGHT be to somehow recognize the sticking solenoid condition, and compensate to allow the oil pressure to say within spec. Only speculation there on my part.

But IMO the last part about the production process being modified can only be referring to some improvement to their engine/part cleaning. They're focused in this TSB on the root cause of the low oil pressure issue being contamination, and only contamination reduction makes any sense to me for that last sentence
 
well it looks like the fix is an updated part and software update to the PCM/ECU. I'm not sure. The verbage is a little ambiguous
The engine oil solenoid valve PYFA-14-440C is not an updated oil pressure control valve for the TSB, but only the newer version since Mazda introduced cylinder deactivation since 2018 MY, presumably to meet the lowered overall oil pressure in the system to accommodate the CD.

Mazda believes the DTC P0524 (Engine oil pressure too low) and DTC P055F (Engine oil pressure malfunction) CELs is caused by “the contamination in the engine oil which may cause the engine oil solenoid valve to become stuck, resulting in improper operation of the oil pump and improper oil pressure”. To resolve the problem, “The control software of the PCM has been modified to eliminate this concern. In addition, the production process has been modified to reduce contamination in the engine oil solenoid valve, oil pump, spacer and oil filter.”.

To me, changing the PCM to eliminate the concern means Mazda is trying to mask the problem and raise the threshold to trigger the CELs. Modifying production process to reduce contamination is only a patching job which can’t fix the root cause, the lowered oil pressure overall just for the CD.

So why the oil pressure control valve won’t get sticky in those non-CD 2.5L with the old production process which may cause contamination?
 
contamination during use. Esp since it's affecting vehicles made in both Japan and Mexico
If the contamination during the normal use would make oil control valve sticky, you have much bigger problem ⋯
 
…But IMO the last part about the production process being modified can only be referring to some improvement to their engine/part cleaning…
Again, your assumption is invalid and based on wild speculation. The word “process” can have such a wide range of meanings that no one can know exactly what it refers to without clarification from Mazda. You might be correct, but it could also refer to a different machining process/assembly order etc. Believe whatever you want, but you logic is faulty.
 
Again, your assumption is invalid and based on wild speculation. The word “process” can have such a wide range of meanings that no one can know exactly what it refers to without clarification from Mazda. You might be correct, but it could also refer to a different machining process/assembly order etc. Believe whatever you want, but you logic is faulty.
Frankly it's amazing to me that you would incinerate what I've posted (apparently) over my use of the word 'cleaning'. It's totally obvious that I don't have any idea exactly what modification Mazda made to their production process, so I chose to use the word 'cleaning' in a generic sense to describe whatever they did (i.e. clean up the contamination).

Whatever process modification they made is totally unimportant when compared the information that actually matters a great deal to owners of these engines. And that is the admission by Mazda that there had been 'contamination' in the production process which was unacceptable enough to cause the automaker to make the change. No 'wild speculation' about that, because it's right there in print in the TSB. All that really matters (to me anyway) is the possibility of contamination being present in our engines, not what they did to eliminate it.

But if 'cleaning' is that offensive to you, I'll use the word 'something' instead, because it doesn't matter to me a bit. I've had my say about this, and won't be doing any more back and forth on it.
 
Guys, the reasons we all worry about CD is long term longevity and reliability.

Let's all post our mileages driven on our Mazda's with CD and see if anyone has experienced any issues with CD.

I'll start. Mine is a 2020 CX5 2.5L with CD. It's presumed mine already has the software fixed installed from factory and currently done 10k miles with no issues. I never felt CD during city or highway driving.
 
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