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

I just checked my VIN number (production date July 2018) on the Mazda Canada website and at the present time the recall hasn't been listed here in Canada yet.

Wade
 
Just checked.
I see the recall info as well (new 2019 CX5 bought 4 weeks ago)

Also a second recall showed up

Recall: 3619F
Date: Jun 27, 2019
NHTSA: #19V496
Status: Incomplete; Remedy not yet available
Details:

Recall: UNDERCOVER WELDING CONCERN

Safety Risk: In the worst case, the metal bracket may fall off from the vehicle, creating a road hazard for other users, increasing the risk of a crash.

Repair: Your Mazda dealer will replace the undercover. The repair will be performed at no cost to you.
 
I*m getting both recall notices as well. Hopefully this takes care of the issue.

As long as the rocker is still in place it should. I imagine the dealers will assume the rockers are in place if non of the symptoms appeared. I wonder if my dealership will remember when I showed them the rocker arm bulletin 8 weeks ago, when they had no idea about it and was the first time they saw it. I will call on Monday to make an appointment.
What is an undercover? I didn't have that recall.
 
Interesting that I had only one recall notice yesterday (rocker issue), then two this morning (rocker issue & undercover welding issue), and now my MyMazda app is showing only one recall notice again (rocker issue). Im still bringing in my vehicle to get fixed for the rocker issue, but I wonder if the uncover welding issue will still need to be addressed or not as well. We shall see...
 
Just returned from a two week 3200 mile road trip. The Mazda performed well. Myself and my wife now feel a litle more confident with the vehicle. I can say that the new engine with the reflash appears to have fixed the issue. At least for now. After reading the posts of the last few days it appears that Mazda has FINALLY decided to do a recall. This is awesome news.
 
The thing is, the pcm update hid the real problem that the rocker arm was not on. If not for Go Hawks, jjm86m would still be driving with a missing rocker.

MyFirstMazda, I wouldn*t say that the PCM reflash *hid* the issue. If your car has already experienced the rocker arm displacement, you will still have the same results at higher RPMs. The car will still go into limp mode. The reflash supposedly changes the logic to adjust the oil pressure to the lifter in question. This will prevent the rocker arm from dislodging. Hence, preventing the sensed *misfire* on the cylinder. There is danger of just doing the reflash without removing the valve cover and actually verifying the rocker arm is in place. If the vehicle does indeed have the rocker arm dislodged but the owner doesn*t realize it, they will get the reflash and have a false sense of security thinking their car is in no danger of trouble since they (the customer) followed through with the recall. I am not sure what the protocol is for the shops when doing the recall work, but I would hope that they are mandated to physically look at the rocker arms. I apologize in advance if I misunderstood what you were trying to say in your post.
 
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I received a free CARFAX membership through the dealership when I leased my vehicle. The CARFAX report is showing both recalls - for the rocker issue and the undercover welding issue.
 
According to the explanation of Mazda-Japan, it is a software glitch.
Not that I have evident for or against it.
 
from what I understand Cylinder deactivation occurs when load is light, at steady speed between 20-50 mph (give or take)
I'm going to be a bit more heavy footed than usual until I get the update applied ;)
that along with mountainous terrain and the occasional trailer pull might keep CD from kicking in too often!
 
between 1200 to 3500 rpm and certain lower torque. According to the tech paper I saw. No mention of speeds.

The pcm is the master control.
Short description is that during CD triggering, the oil pressure is used to control the release of a lock pin. The effect is the rocker arm is 'free' from on one side and the valve spring pushing on the other side of the rocker arm closes the valve.
Reverse has to happen when CD stops.
Pretty slick design but seems oil pressure is the important part to control the whole process. Given that mechanical parts are all ok.
 
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.
 
Sounds very much like the GM design.
By the way, on GM trucks one can guarantee no CD is happening by switching into towing mode or the manual 5-gear mode. You lose converter lock and one gear, but it is quite alright for city driving.
Not sure if it is possible to accomplish with Mazda transmission.
Logically thinking, the aftermarket programmers or plug-in devices for CD deactivation for Mazda ECUs must be on the way. They did help GM owners quite a bit.
One more thing I wanted to mention is that we have not had a collapsed lifter (lash adjuster) yet in Mazda. I am sure it is on the way as well.
 
just bought new GTR yesterday..how do I see if it's affected? NHTSA is showing no recalls

Mine is the same way when I enter the VIN for my GT Reserve. Makes me wonder if something like that undercover welding issue affects all CX-5 trims or only certain ones.

You can search that website by Vehicle (2019 Mazda CX-5.)
That will take you to a screen showing 76 Manufacturer Communications for the FWD and 76 for the AWD.

Click this to see the 76 Manufacturer Communications for the AWD.

I have found no way to filter this by trim level or by engine type (NA or Turbo).
I signed up to My Mazda 3 months ago (but don't have the app on my phone) and have received nothing regarding any recalls.
 
According to the explanation of Mazda-Japan, it is a software glitch.
Not that I have evident for or against it.

I was reading some of the Mazda Mfr Communications on the NHTSA website. One of them spoke of issues with Powertrain Control Modules (PCMs) made by Mitsubishi. Makes me wonder if they subbed these out to anyone else.
 
Just returned from a two week 3200 mile road trip. The Mazda performed well. Myself and my wife now feel a litle more confident with the vehicle. I can say that the new engine with the reflash appears to have fixed the issue. At least for now. After reading the posts of the last few days it appears that Mazda has FINALLY decided to do a recall. This is awesome news.
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?
 
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