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

From the first post "Mazda corporate was sending the tool to my dealership to reprogram the PCM."
Not sure what to read into that, but there it is.

I sent a link to this thread to Jalopnik.
 
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I made an online service request for the PCM reprogram. No way dealers are unnaware of whats happening. There is a link right on my dealers service page which you type in a VIN #, our CX5 lists the recall for rocker arm immediately.
 
I made an online service request for the PCM reprogram. No way dealers are unnaware of whats happening. There is a link right on my dealers service page which you type in a VIN #, our CX5 lists the recall for rocker arm immediately.
I happened to have an appointment for 22.5k service which was set up before I found out about the rocker recall. Called the dealer this morning and they added the fix to the service no problem. Going in two weeks
 
The first person to have the the rocker displacement didn't know it was off. His car went into limp mode and he thought it was from hitting the red line. He brought it to the dealer, they reprogrammed the PCM and he drove it ever since without any symptoms. After Go Hawk discovered the real issue, he and others on this thread told him to have the dealer check the rockers. He did, after a lot of hassle and low and behold they found the rocker off. Then they replaced his motor.

This is his first post about the issue, was back in April.
https://www.mazdas247.com/forum/sho...e-at-Redline&p=6641913&highlight=#post6641913

MyFirstMazda....I did read Go Hawks's OP carefully. What I was saying is that you can now check to make sure your CX-5 does not have a dislodged rocker arm by driving up to 70-80MPH(I think 4 cylinders are needed for this speed) or have the car in sport mode and go hard on the accelerator(pretending to pass someone, like Go Hawks did ). If the car can respond to this driving conditions, then you can assume the rocker arm is still in place. I plan to get my CX-5 reprogrammed for the PCM per the recall, then I will perform the tests mentioned to make sure my rocker arm is still in place.....I recommend others to do the same.
 
Anyone get a recall letter on this yet?? I just ran our VIN on Safercar.gov and it shows the recall for our 2018 CX5.
 
if the rocker arm has fallen it doesnt really matter if the pcm hides anything.
The engine will not run normally from mechanical standpoint. You will notice it.
Then its a new engine time most probably for new cars. Dealers usually dont take the time and most may not have the personnel onsite to remove head from engine block, check valves, seats, clearances, send to repair shops, etc.
The easier route for new cars is new engine to be put it.

cz5gt as the original poster of this thread and one who has experienced this issue, I can assure you that the engine will continue to run normally until you reach a high enough rpm that the PCM senses what it thinks is a misfire and then (and only then) it will throw the car into limp mode. In my case it was between 5500 and 6000 RPM.
 
Thanks for reporting back.

I guess my question is still why Mazda wants to go more expensive way replacing the entire engine, but not just have mechanic simply put the fallen rocker arm back to the position in addition to the PCM firmware update?

I can't answer that question for every situation. But in our case, the problem was still in its infancy and Mazda corporate wanted the engine returned for help in troubleshooting the issue.
 
CD failure rate:

The question we all want to know is how rare or widespread this CD related failure is.
I have been searching the internet to see if there are reports of Mazda CD failures associated with the 6 and the CX-5 from News outlets, but nothing came up beside forum discussions, this site included. So does this mean the problem is rare?



I came across a Consumer Report Used Cars magazine today and CR gave the 6 and the CX-5 both an "Excellent" (highest) rating for reliability across all categories including Engine Minor and Engine Major for model year 2018. So does this mean the problem is rare?

Let me crunch some sale figures relative to the number of reported failures to get an idea. To be clear, my assumption may not be correct, those that are concerned can chime in.

Go Hawks first reported the CD issue in his original post dated 5/3/19 and he said "For the year model 2018, Mazda added cylinder deactivation to the engines that are installed in both the CX-5 and the Mazda 6 models. Unfortunately this system is what caused the trouble for us and, at last count, at least 26 other customers that Mazda has confirmed"

Assumptions:
1. I don't know if 26 failures included both CX-5 and 6, but let's assume 26 are all CX-5 failures (worse case).
2. 26 failures are nationwide (I can't imagine this many failures reported at one dealership Go Hawks went to)
3. We know CD was introduced beginning model year 2018 and after and since Go Hawks OP was 5/3/19, I will use March 2019 as a cut-off date to calculate sales figures.

Sales figures for CX-5:
2018: 150,622 units sold (according to "Car and Driver")
Jan 2019: 10,652
Feb 2019: 13,377
Mar: 13,465
Total: 188,116 units sold for the entire year of 2018 and up till March 2019.

So we are looking at 26 CD failures out of 188,116. This is a 0.014% failure rate or 1 failure out of 7,235 units. Again, my assumption may not be correct, those that are concerned can chime in. This sounds rare, but I still worried for my 2019 CX-5 Touring.

My reference of 26 failures was from November 2018. That was the last count that my dealership had as of then. I was also told at that time by Mazda that they had 2 providers of PCMs and one of those had the wrong program on theirs. So, if this is true, its anyones guess how many vehicles are out there with this possible issue. And if you are simply doing city driving and never push the engine to a high enough RPM you may never experience the limp mode issue. But your vehicle still may have the dislodged
rocker arm. I have been trying to get Mazda to recall these vehicles ever since mine was in the shop getting a new engine. So I am extremely happy that hey are finally doing it.
 
The rocker arm problem should be relative rare, as the cylinder deactivation itself should rarely happen based on its preset criteria.

But how often this problem happens is not the point. It's its unpredictable nature which is very dangerous like OP keeps emphasized. You'll never know when the rocker arm has fallen off, until at the time you need full power and found the engine falls into the limp mode! I hope Mazda has found out the real cause of the problem, and design a fall-safe hardware where even if the oil pressure varies out of the specified range, the rocker arm still would stay put. Remember oil pressure keeps changing during engine operation, and the use of different viscosity, temperature, and even the low oil level also contribute different oil pressure. Controlling oil pressure with software alone simply is not a feasible task, and the fact of this problem happening is the proof that the PCM software simply can't cover every situation on oil pressure changes.

Thank you for having my back yrwei52. You are exactly right, how rare or widespread the issue is really isn't the point. The real point is you have no indication of if or when the rocker arm fell off and if it did you could be presented with a deadly situation. And, since they have now issued a recall, I think its safe to say the number of these vehicles is much greater than 26. In fact we know its at least 27. We had one from this forum that had the same issue and had his engine replaced also.
 
Can you test out the car to determine whether the rocker arm is still in place by pushing the car to 70-80 mph? or pretending to pass someone on the freeway? If you push the car and it responds normally, then you don't have a dislodged rocker arm.

That is exactly how I proved it to the dealership when I took mine in originally. Mine would do it when RPMs were between 5500 and 6000 and held there for a bit. You need to push the engine hard enough that it will cause the affected cylinder to have a bad fuel/air ratio. This is what will throw it into limp mode due to the PCM sensing a false misfire on that cylinder. Usually cylinder 4.
 
From the first post "Mazda corporate was sending the tool to my dealership to reprogram the PCM."
Not sure what to read into that, but there it is.

I sent a link to this thread to Jalopnik.

When they had my car and they determined that they needed to reflash the PCM, I was told by the dealership that Mazda only has a couple the the "tools" needed for the reflash. It took them a few days to get this "tool" and finally reflash my PCM. That is why I went ballistic on them when I asked if they were reflashing all of the vehicles on their lot while they had this tool on site. They said they did not have permission from Mazda to do that and mine would be the only one that they would do at that time. I also told the Western U.S. Technical Rep. that I thought it was B.S. that Mazda would not allow the dealership to reflash all of the possible affected vehicles. He told me that they were not sure which ones were affected at that time. My reply to him was "My point exactly! It makes no sense to me that you would not just reflash every one of these vehicles if you know for sure that is the fix."
 
I happened to have an appointment for 22.5k service which was set up before I found out about the rocker recall. Called the dealer this morning and they added the fix to the service no problem. Going in two weeks


Find out what the protocol is for the recall work. If it calls for just reflashing the PCM, force them to actually remove the valve cover and physically look. The reflash will do nothing for you if the rocker arm is already dislodged.
 
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When they had my car and they determined that they needed to reflash the PCM, I was told by the dealership that Mazda only has a couple the the "tools" needed for the reflash. It took them a few days to get this "tool" and finally reflash my PCM. That is why I went ballistic on them when I asked if they were reflashing all of the vehicles on their lot while they had this tool on site. They said they did not have permission from Mazda to do that and mine would be the only one that they would do at that time. I also told the Western U.S. Technical Rep. that I thought it was B.S. that Mazda would not allow the dealership to reflash all of the possible affected vehicles. He told me that they were not sure which ones were affected at that time. My reply to him was "My point exactly! It makes no sense to me that you would not just reflash every one of these vehicles if you know for sure that is the fix."

This is almost comical. They're trying to minimize their cost. So, no engine replacement, possibly no checking for a dislodged rocker arm, no flashing of existing lot vehicles. Looks like another example of another failed attempt of CDA. All this to gain a measly mile or 2 per gallon.
 
Our 2018c-x5 gt is 10 months old with 2,764 miles. I spoke with our Florida dealer Service Manager yesterday. He said even though the recall isn't officially out yet (which Mazda corporate verified} he was updating cars on his lot and could do our firmware update on this Friday. Since we have low mileage and never had it go into limp mode and or no engine lights come on. Is it safe to say the rocker arm is ok or does it have to be physically check?
 
I was told the same that the recall is not officially released whatever this means. may be that they are not sending mails yet.
You have to ask the dealer about it explicitly. Suggest first to chek by phone before scheduling visit.
 
Our 2018c-x5 gt is 10 months old with 2,764 miles. I spoke with our Florida dealer Service Manager yesterday. He said even though the recall isn't officially out yet (which Mazda corporate verified} he was updating cars on his lot and could do our firmware update on this Friday. Since we have low mileage and never had it go into limp mode and or no engine lights come on. Is it safe to say the rocker arm is ok or does it have to be physically check?

I would push to have it checked. Maybe print out this thread and show them why. Nothing is 100% without a visual.
 
Most dealers are probably reluctant to drop the head cover because somebody has to pay for new gasket after +labor.
But I would agree, best way is to look visually inside.
All of this is a shame on Mazda. Just doing only pcm update without visual inspection be a part of the recall.
 
I think I bought a new CX-5 last night. After about an hour of filling out paperwork, I was on my way to finance guy. The sales manager come up and says "I hate to tell you this, but I cannot release the car to you because of a just received recall, we think it will be about a week to "get the fix". He continued "you can cancel the sale now or proceed and it will not finalize until you take possession". After probably a dozen hours of research, You Tube, and internet shopping I decided to proceed. Talk about being frustrated! I will see what kind of news comes out this week and decide what to do. I wonder how dealers will handle this--will they tell customers up front before the test drive, or wait until the very end of the process like what happened to me.
 
I think I bought a new CX-5 last night. After about an hour of filling out paperwork, I was on my way to finance guy. The sales manager come up and says "I hate to tell you this, but I cannot release the car to you because of a just received recall, we think it will be about a week to "get the fix". He continued "you can cancel the sale now or proceed and it will not finalize until you take possession". After probably a dozen hours of research, You Tube, and internet shopping I decided to proceed. Talk about being frustrated! I will see what kind of news comes out this week and decide what to do. I wonder how dealers will handle this--will they tell customers up front before the test drive, or wait until the very end of the process like what happened to me.

This is an indication of how serious Mazda considers this problem.

Let's wait to see how they handle the recalls. There's no reason to think that Mazda is going to be cheap and stupid about it.
 
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