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

The pcm update does not remove the limp mode or masks anything.
It just updates the software control for oil pressure which is used for CD control (on/off) according to details.

I am staying behind my quote that if you get your rocker arm fallen you will notice it sooner or later. The least there would be different sounds from the engine.
Its not the end of the world. There are much worse recalls like takata airbags, cars getting on fire, etc.
Just drive on sport or manual mode for a test if you are so worried.

You are correct in your statement that it doesn't mask anything or nullify limp mode. But you are way off base with your assumption that sounds from the engine are different or even noticeable performance in every day driving. In my case and in JJM86M we noticed nothing wrong with our vehicles until limp mode was activated. My wife and I had put 9000 miles on our car before this happened, and we had no indication af anything wrong. Performance or engine noise never changed from day we bought it. And to say there are much worse recalls such as the air bags or cars catching on fire is quite comical to me. If your car goes into limp mode while passing a vehicle and you have oncoming traffic, you may cause an accident. Which would hopefully activate your airbags and quite possibly cause a fire. So I will leave it to you to judge again which is worse.
 
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I was in the market for a CX-5 and having previously owned a 2003 Accord with faulty designed transmission, I've gone through "manufacturer fixes" that only delay or mask a defective design.

I want to make sure this is not the case CX-5. I know it's early to say, but any opinions if the PCM fix should solve the problem? And if I buy a used one, would a car with this condition prior have more wear than those that have had the PCM fix earlier?

Interestingly, a Certified Pre-owned has a 7y/100K powertrain warranty while a new one has 5y/60k.
 
I was in the market for a CX-5 and having previously owned a 2003 Accord with faulty designed transmission, I've gone through "manufacturer fixes" that only delay or mask a defective design.

I want to make sure this is not the case CX-5. I know it's early to say, but any opinions if the PCM fix should solve the problem? And if I buy a used one, would a car with this condition prior have more wear than those that have had the PCM fix earlier?

Interestingly, a Certified Pre-owned has a 7y/100K powertrain warranty while a new one has 5y/60k.

If you like the latest CX-5 design and want to buy a used one, you should buy model year 2017 (Mazda started 2018 with CD feature).
It is normal to have a Certified Pre-owned to have a longer warranty period - it serves as an incentive for you to buy it.
Whether if PCM fixes the problem is anyone's guess. It supposed to prevent the problem from happening and I am sure Mazda hope for the same too. Mazda just released the new 3 sedan and hatchback, both with CD feature(not to mention the 6 also has CD too) - too many Mazda models have CD feature now and Mazda better get it right. You also have 3 years manufacture warranty(you can also buy more years of warranty if you want a peace of mind). BTW...I just came across a recent post here and Honda CRV has rocker arm issue too.
 
just a quick note.
After the pcm update it seems reset are both of the average mpg counters to 0, the homelink setup for an already set garage opener and some of the settings in the infotainment, more precisely the active street sign recognition is back to default (on). at least on my car.

by the way, the second recall for the bad weld part (unrelated to the rocker arm recall) seems gone from carfax.
May be as somebody mentioned it was a mistake.
 
just a quick note.
After the pcm update it seems reset are both of the average mpg counters to 0, the homelink setup for an already set garage opener and some of the settings in the infotainment, more precisely the active street sign recognition is back to default (on). at least on my car.

by the way, the second recall for the bad weld part (unrelated to the rocker arm recall) seems gone from carfax.
May be as somebody mentioned it was a mistake.

They disconnected your battery before the PCM update.
 
Wishful thinking. I don't think Mazda would disable CD feature because of legal issue. That would violate emission footprint that they already filed for and it would violate the advertised MPG on the sticker window. However, the same cannot be said for engine Stop/Start feature where there is usually a button to disable it. I would pay someone $500 right now to disable my CD feature forever.

I don't know. They don't say they are disabling CD, they are adjusting the oil pressure so the rocker won't fall off. But if the system doesn't drop the oil pressure when not under load, I don't see how CD can kick in.
 
I was in the market for a CX-5 and having previously owned a 2003 Accord with faulty designed transmission, I've gone through "manufacturer fixes" that only delay or mask a defective design.

I want to make sure this is not the case CX-5. I know it's early to say, but any opinions if the PCM fix should solve the problem? And if I buy a used one, would a car with this condition prior have more wear than those that have had the PCM fix earlier?

Interestingly, a Certified Pre-owned has a 7y/100K powertrain warranty while a new one has 5y/60k.

By now, you have read the advice that Tran7270 gave you and it is really good.

BTW, the Certified Pre-Owned warranties on used vehicles aren't free. It will add a couple thousand dollars to the net price. But I think in most cases, they are a good idea. I love warranties. They give me a lot of peace of mind. It's like having Term Life Insurance on the vehicle. You are betting that the vehicle will die, the dealership is betting that it won't.

I know that the company usually comes out ahead financially but hey, that's the way business works. If it was a money loser, we would not have the option to purchase additional coverage.

I have extended warranties on my MX-5 and CX-5. Six years, 100,000 miles, bumper to bumper, excluding normal wear items. I actually worked with the dealership for large discounts on both vehicle's warranties.

All of this is just what ever makes you feel good. Some people feel that extended warranties are a waste of money and perhaps they are in most cases. I choose to not take those risks.

But again, the advice Tran7270 gave you insures that what ever you do, you win in the end. You will get to drive a really great vehicle, relatively worry free. No vehicle is perfect so we have to throw "relatively" in there. :)
 
Going to get my PCM update tomorrow. Service Department told me it would be 1.5-2 hours, as they need to do the update and inspect the vehicle. Well see what ends up happening.

And looks like the undercover welding issue recall has been removed from MyMazda app and CARFAX on my end. The dealership didnt mention anything about it when I called to schedule my appointment, either. False start for that recall, or no longer an issue?
 
I had mines completed yesterday along with an oil change/tire rotation. Took about an hour. I revved the crap of it and took it up to 95mph for a split second. Everything seems fine.
 
This is rather disappointing. I am glad they are actually recalling these vehicles but they really need to be removing the valve cover and taking a look. If a customer already has the rocker arm off and don't realize it, this update does nothing for them. The damage has already been done and the dangerous situation still exists. This may actually make the situation worse given the false sense of security a person would have after having the recall work done and thinking they are no longer in danger of anything happening.

It behooves everyone with a 2018/19 2.5NA to put it in manual and wind it out to 5k and keep it there for a minute, whether it's had the fix or not.

What are you waiting for?
 
so, to those that have the software update for CD... can you tell or hear a difference with
the engine now ??
Is this going to make the oil pump wear out sooner ?? or blow out oil everywhere eventually ??

Wonder how much pressure they increase it by......... 1 lb, 10 lbs ??

I'm going to call mazda tomorrow for the update
 
* I'm going to call mazda tomorrow for the update
And find out the version number of the updated PCM firmware for the recall.

You should try to have your dealer doing a visual of the rocker arms.
 
probably you can't find it on your own.
At least it doesnt show on forscan when I check.
I can compare as built parameters before and after but it wont get much useful info except which ones were changed. And they are not in human readable form.

My recall work invoice it doesnt show the version but some people mentioned they have it on the invoice paper.
 
It behooves everyone with a 2018/19 2.5NA to put it in manual and wind it out to 5k and keep it there for a minute, whether it's had the fix or not.

What are you waiting for?

I second this. If you've had (or are going to get) the recall done, I'd find an open road suitable for testing, and do just what shadonoz says. If the PCM has been updated, but the engine hasn't been opened up, run the test. If it does go into limp mode, take it back to the dealer and they'll fix it accordingly. If it doesn't, then the issue is resolved.

I think that Mazda should be the ones to perform the test after updating the PCM as part of the recall. But until they start doing that, there's no reason that owners can't do this test themselves (provided they have roads suitable to perform this test on).
 
I second this. If you've had (or are going to get) the recall done, I'd find an open road suitable for testing, and do just what shadonoz says. If the PCM has been updated, but the engine hasn't been opened up, run the test. If it does go into limp mode, take it back to the dealer and they'll fix it accordingly. If it doesn't, then the issue is resolved.

I think that Mazda should be the ones to perform the test after updating the PCM as part of the recall. But until they start doing that, there's no reason that owners can't do this test themselves (provided they have roads suitable to perform this test on).

Just to be totally clear, this test is not about vehicle speed, it is about engine speed. You can do this in 4th on the interstate. You can do it in 2nd on a lonely highway and not get above [I dunno] 30 or 40 mph. Get the revs up and keep them there.

And if you go into limp mode, please post it here.

But as sm1ke says, be safe!
 
It behooves everyone with a 2018/19 2.5NA to put it in manual and wind it out to 5k and keep it there for a minute, whether it's had the fix or not.

What are you waiting for

For clarity -

when you say keep it there for a minute, do you mean literally 60 seconds?
 
For clarity -

when you say keep it there for a minute, do you mean literally 60 seconds?

No, not literally a minute. Just a few seconds, Maybe between 5-15 seconds. Remember, all you are trying to do is see if the computer senses a *misfire* on a cylinder due to the air/fuel ratio not being correct. So it may sense it as soon as you get above 5500 rpms or it may take it a few seconds to sense it. Mine happened when I was passing a vehicle. I was accelerating and keeping the RPMs high when it would go to limp mode.
 
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