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

yrwei52 said:
Actually it*s a two-cylinder with CD.

Yeah I*d seen that 3-wheeler BMW when I was a kid, but have never ridden in one.
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I'll display my ignorance here.

Why do you say it's a two-cylinder with CD? Is it because only 2 of the cylinders are always on? Would one refer to the Mazda as a two-cylinder with CD for the same reason?

Regarding the Beemer...we camped at Lake Michigan in the 50s and 60s, and the guy who managed the place (maybe the owner) would toodle around the campground in it and give us rides.
 
Avoidin Deer said:
I'll display my ignorance here.

Why do you say it's a two-cylinder with CD? Is it because only 2 of the cylinders are always on? Would one refer to the Mazda as a two-cylinder with CD for the same reason?

Regarding the Beemer...we camped at Lake Michigan in the 50s and 60s, and the guy who managed the place (maybe the owner) would toodle around the campground in it and give us rides.
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Yes.
 
I just can't imagine (in my head) a 3 cylinder, 90 cubic inch (1.5l) engine, in anything as big and heavy as an SUV.
Honda's 1.5 engine is so small and anemic that it can't produce enough heat to warm up the cabin or defrost a windshield in the winter.
What is Ford's engine going to do in that regard? And how much heat can it produce when only 2 cylinders are firing?
BBrrrrrr.
 
Buzzman12 said:
I just can't imagine (in my head) a 3 cylinder, 90 cubic inch (1.5l) engine, in anything as big and heavy as an SUV.
Honda's 1.5 engine is so small and anemic that it can't produce enough heat to warm up the cabin or defrost a windshield in the winter.
What is Ford's engine going to do in that regard? And how much heat can it produce when only 2 cylinders are firing?
BBrrrrrr.
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My Bugeye Sprite was 948CC, or 58CI. It was a 2-seater.
This is the same cast iron engine they put in the Nash Metropolitan, also a 2 seater with a "jump seat" for 2 kids.

I'd never done this conversion before. Nor had I done the conversion on the Honda 1.5L
That's tiny!!!
 
Yup.
1 litre is 61 cubic inches.
A 5 litre V8 sounds huge, but it's only a 305 CI engine.
The old 427 CI would be a whopping 7 litres. Sounds huge today.
That's why I'm always impressed when I see something like Ferrari's 3.9L (238CI) V8 pumping out about 650 horsepower.
For comparison, my first car was a 1965 Chevy with a straight 6, 250 CI, pumping out about 150HP. Coupled to a 2 speed automatic, it was a dog.
It saw more action in the backseat than it did at a green traffic light.
 
2020 Mazda CX-5 Press Release mentions CD system display.

Now you can see when CD kicks in and out. Wonder if this feature can be implemented on a 18 & 19 CX-5 through a SW update. I was hoping Mazda implement a "CD disabled" button(I know...wishful thinking... Mazda did not put one on 2020 3, so go figure). I think if Mazda get rid of CD, sales will improve.

"The seven-inch full-color, touchscreen display with Mazda ConnectTM receives a new Cylinder Deactivation System display, which will help show the fuel efficiency of the four-cylinder Skyactiv-G 2.5 engine"


https://insidemazda.mazdausa.com/pr...-continues-to-separate-itself-from-its-class/
 
Buzzman12 said:
As if Honda doesn't have enough problems, now the newer 2019's (CR-V) has a battery problem.
If left for more than a few days without running, the battery will be dead.
It's not the actual battery either, but a parasitic drain issue. Every post I've read on the problem has Honda and dealers deflecting the problem as "normal" with today's high tech cars.
Really? A brand new $35,000 car that dies after 3 days, and it's normal?
Honda telling owners to get a trickle charger, or starting and running the car everyday for 10 minutes. Wow.
I've read a lot of posts from some very pissed off people about this.
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I read somewhere that break in period for a new Honda Civic 1.5T was 28000 miles. Yes and expected lifespan is 3.5 million miles lol. Honda is best at fooling people.
 
I currently have a 2017 CX-5 GT,no problems, engine runs great. Would like to get a 2020 CX-5 Sport for wife but with all the problems with cylinder deactivation we are concerned that Mazda does not have an acceptable solution for correcting problems.
Is the soft wear upgrade a reliable long term fix on the 2019- 2020 yr. models? Is anyone with a 2019 or 2020 CX-5 having any problems with the CD mode? Getting a headache from reading all 48 pages of posts on this matter.
Thank You.
 
georgem44 said:
I currently have a 2017 CX-5 GT,no problems, engine runs great. Would like to get a 2020 CX-5 Sport for wife but with all the problems with cylinder deactivation we are concerned that Mazda does not have an acceptable solution for correcting problems.
Is the soft wear upgrade a reliable long term fix on the 2019- 2020 yr. models? Is anyone with a 2019 or 2020 CX-5 having any problems with the CD mode? Getting a headache from reading all 48 pages of posts on this matter.
Thank You.
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I havent read about a single issue due to long term effects of cylinder deactivation on a Mazda vehicle. Too soon to tell. Its going to take years and over 100k miles on vehicles to see if issues (if any) crop up. The rocker arm falling off due to the issue identified is a short term problem unique to Mazda. Jury is out on oil consumption, engine mount issues, etc as that will take a lot of mileage for that to crop up (if these engines are even susceptible to issues experienced by other manufacturers).

Thankfully 4 cylinder engines are balanced much better than V6s. I dont foresee Mazda having any motor mount issues due to CD for that reason. Oil gets past piston rings when there is no combustion in the cylinder. Thats a fact. As long as Mazda programmed the system to minimize oil consumption there shouldnt be any negative long term effects (low oil, stuck piston rings, fouled spark plugs).

My mother in laws 2018 was potentially effected but we got the PCM flashed to correct it. No problems with about 15k miles on the clock. Im confident they got it right with the software update.
 
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georgem44 said:
I currently have a 2017 CX-5 GT,no problems, engine runs great. Would like to get a 2020 CX-5 Sport for wife but with all the problems with cylinder deactivation we are concerned that Mazda does not have an acceptable solution for correcting problems.
Is the soft wear upgrade a reliable long term fix on the 2019- 2020 yr. models? Is anyone with a 2019 or 2020 CX-5 having any problems with the CD mode? Getting a headache from reading all 48 pages of posts on this matter.
Thank You.
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I had to laugh at your "wall of data" observation. I've run into the same thing myself on other stuff, but always seem to learn something tangential to the original subject.

I've been following these threads from the beginning (nearly bought a 2018 myself) and have yet to read of anyone who has had the software upgrade report back any issues.

Some folks noted an increase in mileage and a slightly peppier feel.
Some folks noted a decrease in mileage and a little sluggishness.
Dunno if that tells us anything.
 
georgem44 said:
I currently have a 2017 CX-5 GT,no problems, engine runs great. Would like to get a 2020 CX-5 Sport for wife but with all the problems with cylinder deactivation we are concerned that Mazda does not have an acceptable solution for correcting problems.
Is the soft wear upgrade a reliable long term fix on the 2019- 2020 yr. models? Is anyone with a 2019 or 2020 CX-5 having any problems with the CD mode? Getting a headache from reading all 48 pages of posts on this matter.
Thank You.
Click to expand...

Too soon to tell. You pays your money and you takes your chances.
 
georgem44 said:
I currently have a 2017 CX-5 GT,no problems, engine runs great. Would like to get a 2020 CX-5 Sport for wife but with all the problems with cylinder deactivation we are concerned that Mazda does not have an acceptable solution for correcting problems.
Is the soft wear upgrade a reliable long term fix on the 2019- 2020 yr. models? Is anyone with a 2019 or 2020 CX-5 having any problems with the CD mode? Getting a headache from reading all 48 pages of posts on this matter.
Thank You.
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As long as Mazda doesnt design a physical holder or some barrier like other manufactures to prevent the rocker arm falling, Im the one not going to feel comfortable the problem has been truly resolved. On the other hand, if you dont keep the car for very long like me, I feel you dont have to worry too much about the cylinder deactivation as most problems on CD are from long-term. The only thing may be hurting if any is the trade-in value.

Personally Id check some Mazda models without cylinder deactivation if I really want a Mazda. Some Mazda3 sedans, all CX-3s, and some CX-30s dont have CD. Of course, CX-5 turbo models and CX-9 have no CD either.

And strangely in Canada CX-5 Sport doesnt come with the CD for some reason.
 
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yrwei52 said:
As long as Mazda doesnt design a physical holder or some barrier like other manufactures to prevent the rocker arm falling, Im the one not going to feel comfortable the problem has been truly resolved. On the other hand, if you dont keep the car for very long like me, I feel you dont have to worry too much about the cylinder deactivation as most problems on CD are from long-term. The only thing may be hurting if any is the trade-in value.

Personally Id check some Mazda models without cylinder deactivation if I really want a Mazda. Some Mazda3 sedans, all CX-3s, and some CX-30s dont have CD. Of course, CX-5 turbo models and CX-9 have no CD either.

And strangely in Canads CX-5 Sport doesnt come with the CD for some reason.
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This seems completely negative bullsh*t to me.
 
I believe Toyota uses a small clip to hold the rocker the lifer. That system doesn't depend on oil pressure to assure the rocker doesn't fall off to the side. I would hope that this would be MAZDAs fix for all new engines and the fix for those presently have the problem. A small company like MAZDA can't afford to have issues like this plague them year after year. Ed
 
georgem44 said:
I currently have a 2017 CX-5 GT,no problems, engine runs great. Would like to get a 2020 CX-5 Sport for wife but with all the problems with cylinder deactivation we are concerned that Mazda does not have an acceptable solution for correcting problems.
Is the soft wear upgrade a reliable long term fix on the 2019- 2020 yr. models? Is anyone with a 2019 or 2020 CX-5 having any problems with the CD mode? Getting a headache from reading all 48 pages of posts on this matter.
Thank You.
Click to expand...

We won't know for many years. If you are going to keep it 5 years or less I don't think it's a reason not to get one. Had I saw the huge recall earlier, prior to me buying mine, I would not have bought it. However I love my 2018 CX-5 and I am no longer concerned with CD. My last thought is that I am conservative, sports car like acceleration and many whistles and bells was not my priority. Your wife might prioritize other things in a car so make sure she likes the car she gets. And check the vanity mirror, mine does not have a light and she might not like that.
 
Would prefer a CX-5 non turbo but this rocker arm issue is a no go. How do we know it's not possible for the rocker arm to come loose even in the turbo non CD model? If it's an oil pressure thing maybe being low on oil or starting up after an oil change could do it or an oil pump long term going bad.
 
Tar Heel said:
Would prefer a CX-5 non turbo but this rocker arm issue is a no go. How do we know it's not possible for the rocker arm to come loose even in the turbo non CD model? If it's an oil pressure thing maybe being low on oil or starting up after an oil change could do it or an oil pump long term going bad.
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This doesn*t affect the turbo because there is no CD. There are unique mechanisms to make the cylinder deactivation occur on certain cylinders on the engines that have CD. The other cylinders don*t have the mechanism, so they don*t have the problem, and that includes the non-CD cylinders on the CD engines as well as all non-CD engines..
 
Tar Heel said:
Would prefer a CX-5 non turbo but this rocker arm issue is a no go. How do we know it's not possible for the rocker arm to come loose even in the turbo non CD model? If it's an oil pressure thing maybe being low on oil or starting up after an oil change could do it or an oil pump long term going bad.
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The reason why the rocker arm is fallen is because the hydraulic lifter, or hydraulic lash adjuster (HLA), designed for cylinder deactivation is different from those used on non-CD cylinders. The HLA used for CD has transition states from oil pressure which locks and unlocks a pin to make the HLA either staying firm in normal operation or collapsing in CD mode. The rocker arm dislodged loose is because the HLA lost its minimum pressure against it during the transition states and theres nothing physically to keep the rocker arm in place like other engines. On non-CD cylinders the HLA will never be experiencing this transition state hence chances are very slim to let the rocker arm loose and falling.

From history weve never heard any incidents that the rocker arm is fallen on non-CD SkyActiv-G 2.0L / 2.5L. The HLA on valve train for current SkyActiv-G 2.5T is the same design as the non-CD 2.5L, so the falling rocker arm problem should be a non-issue for 2.5T.

yrwei52 said:
I was about to say that it must be just one of 2 intake rocker arms on cylinder 4 fallen off during cylinder deactivation cycle when the hydraulic lash adjuster releases its lock pin with low oil pressure. I still don't understand how the rocker arm simply would fall off the position during CD cycle, as oil pressure is supposed to be low to release the lock pin and disable the hydraulic lifter, and the rocker arm supposed to be still in position during such situation. I believe Mazda either didn't tell the truth to OP, or Mazda hasn't figured out the root cause of this problem. Again, like EPB TSB, this seems to be a hardware design issue, and it has nothing to do with software which controls the oil pressure. I doubt the "fix" on PCM firmware would truly fix this, just like Mazda's initial attempt of trying to change EPB control module firmware on 2016 CX-5.

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I have not heard of any engine problems with vehicles which have updated ECU CD software, so hopefully it will be ok.

Oil change every 10,000 km and driving (cabpatch). Now I have 27 000 km (16 777 miles).
I guess there are those here who have driven over much more.

It would be good to now your current mileage readings.

PS. And I apologize for my English, I`m using a translator.
 
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Agreed, except there was one person who had the recall done after going into limp mode one time, and later on it was discovered that a rocker arm fell off and necessitated an engine replacement.

Havent yet heard of the problem manifesting after completion of the recall/software update. We have 20k on our 19 (in 6 months), and had the recall done early on, about a month after purchase. No issues whatsoever thus far 🤞🏽
 
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