I wish I could turn off cylinder deactivation

erhayes

Contributor
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2022CX5 PP
No problem. Just another complication. I do feel a hesitation when going from 2 to 4 cylinders when I want to merge quickly.
 
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18 Mazda CX5 AW
No problem. Just another complication. I do feel a hesitation when going from 2 to 4 cylinders when I want to merge quickly.

Was having this problem as well. Car was sluggish and slow to get up to merge on the 19 inch tires.

Switched to 17 inch and improved somewhat.

But since I threw on the 16 inch light rims with 235 70r16 tires, it takes off. Not sure if it was due to dropping the 60 lbs of unsprung weight, or the slight width/height increase of the tires but the CX5 moves now. And the cd kicks in on highway once the cruise control set.

Regardless the reason, the vehicle accelerates and drives alot better now.

Maybe you can get better merge acceleration with superlight 17 or 19 inch wheels.
 
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erhayes

Contributor
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2022CX5 PP
I wonder how much fuel is save with these 4 to 2 returns to 4 Maybe 0.01 gal per 100 miles. This quest for fuel savings via Government is making life more complicated for sure.
 

CarpeDiem

Under Pressure
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Superstitions
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2021 CE Turbo
I wonder how much fuel is save with these 4 to 2 returns to 4 Maybe 0.01 gal per 100 miles….
Well, wild guesses supported by nothing but emotion won’t help us at all. Any fuel savings will depend on the particular application and type of driving, but I found that on a Hemi I owned using it saved about 8% on 1200 mile long trips averaging 70-75 mph. I don’t know how typical that is, but I repeated the test several times.

Whine all we want about CDA, but manufacturers are crippled by CAFE and NOx emissions standards, they have to do something to save fuel and reduce pollution. An easy alternative to CDA is to use 1200 cc engines like some manufacturers do - but would you really want to trade the 2.5 for a 1.2?

Here are several sites with different fuel savings data.



 

HardRightEdg

US 2020 CX-5 Touring AWD Soul Red
I wonder how much fuel is save with these 4 to 2 returns to 4 Maybe 0.01 gal per 100 miles. This quest for fuel savings via Government is making life more complicated for sure.
Well, wild guesses supported by nothing but emotion won’t help us at all. Any fuel savings will depend on the particular application and type of driving, but I found that on a Hemi I owned using it saved about 8% on 1200 mile long trips averaging 70-75 mph. I don’t know how typical that is, but I repeated the test several times.

Whine all we want about CDA, but manufacturers are crippled by CAFE and NOx emissions standards, they have to do something to save fuel and reduce pollution. An easy alternative to CDA is to use 1200 cc engines like some manufacturers do - but would you really want to trade the 2.5 for a 1.2?

Here are several sites with different fuel savings data.



That's all fine and good except Mazda got next to nothing for their trouble CAFE-wise. The 2017 without CA had EPA ratings of 23 / 31 MPG for FWD, 23 / 29 for AWD. For 2018, same generation with CA it's 25 / 31 and 24 / 30, respectively, about a 1 MPG savings.

I don't have any issues with how the vehicle performs with CD. However the same savings could have been accomplished with an 8-speed trans and improve shifting in the process if done well. Modifying the engine and ECU was probably less expensive with no 8-speed already in the Mazda lineup.
 
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CX5 GT
Its not because Mazda wanted to but they had to. They are a small manufacturer with still normal engine displacements. The reason why others with large fleets went on some models to 1.2 while keeping other models with larger engines. and in europe even 3 cylinders toys.

Enjoying the cars while we can because its the end of an era basically. EV will take over sooner or later.
 

erhayes

Contributor
:
2022CX5 PP
The streets here in my town have little rises at the drive through intersections and my CX5 is constantly quickly shifting from 4-2-4. Uggg
 
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CX5 GT
sport mode helps with slow speeds in town.
Have to admit the cx5 is a bit annoying in certain daily town driving.
If one would not want to use the sport mode then not much else you could do except may be change to a Turbo Cx5 as it does not have that annoying switching in slow town traffic, at least its not that pronounced.
With sport mode it keeps the transmission from shifting early
 

HardRightEdg

US 2020 CX-5 Touring AWD Soul Red
The streets here in my town have little rises at the drive through intersections and my CX5 is constantly quickly shifting from 4-2-4. Uggg
That may not be cylinder deactivation per se. If you approach the bump with a foot on the brake or while coasting, you're not shifting 4-2-4. It would be 4-0-4 or 2-0-4, where the 0 is not cylinder deactivation--all pistons are in motion with little or no fuel being injected as is typical with fuel injected engines when the foot is off the gas and vehicle in motion.

If you keep an eye on the real time mpg meter or the cylinder activation display on the screen you should find that 2 cylinder operation occurs under constant light low load with steady pressure on the gas. The real time MPG meter at around the 50-60 range is indicative of CD in operation. If the needle buries at the high end (80 MPG in my vehicle, some say theirs is 100 MPG), that's the 0 cylinder mode.

Now it's possible you might go 2-4 if you approach the bump at the low load constant speed to be in 2-cylinder mode and then accelerate after crossing but you'd have to monitor your behavior in conjunction with the displays.

Further, my skepticism is reinforced by my observations that less than smooth shifting typically does not involve 2 cylinder operation. Slight, brief lugs or jolts occur for me in the first to third gear range when easing off the gas or braking and then reaccelerating where the 2 cylinder sweet spot does not come into play.

Now, while the less than smooth shifting might not be cylinders deactivating per se, it could be systemic encompassing engine, torque converter and transmission control compromises to accommodate CD. That might seem like splitting hairs but when you consider it situationally, whether the vehicle is or was in two cylinder mode, there's some useful information to be gleaned.

Even so, one of the most technically knowledgeable people in this forum has reported lugging when making U turns, a deceleration-reacceleration scenario cropping up in his 2017 pre-CD, so there's more going on that just CD. Frankly, I'm very surprised the term "lugging" almost never comes up in these discussions.

Experiences will vary based on versions of engine, torque converter and trans control software. You'd also have to parse the differences in reports between FWD and AWD. But one thing should be constant--2 cylinder operation is in that low load, steady gas pedal pressure scenario. It's why many report across years that sport mode alleviates the issues--it revs higher and is less prone to finding the 2 cylinder sweet spot at low load and relatively low constant RPMs.

Is my experience terrible? No, it's an occasional annoyance mostly in lollygagging situations. If you have to slog through stop and go rush hour traffic it might rise above the mere annoyance level. A 150 mile back road trip with travel through a few villages presented no annoyances. Beats some janky raspy CVT. However I do wonder if those minor jolts put undo wear on the trans.
 
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HardRightEdg

US 2020 CX-5 Touring AWD Soul Red
If one would not want to use the sport mode then not much else you could do except may be change to a Turbo Cx5 as it does not have that annoying switching in slow town traffic...
There is one thing to try if you don't want to use sport mode.

When stopping behind somebody at a light, leave extra space between you. Once that guy starts to move wait a beat or two before accelerating. I mean how often do find yourself start to accelerate then have to let off the gas because the wagon train in front is lollygagging at a slower pace than expected? Often I bet. In this way you can often avoid the low gear acceleration / deceleration / acceleration cycle that seems to cause issues, at least they do for me. I find working toward a steady acceleration curve alleviates the issues.

Yes, that is one of those annoying "adapt to the tool" techniques but you might find it useful. And occasionally the guy behind you might honk if you're not right off the mark, but that's his problem.
 
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Fredericton Canada
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2018 CX-5 GT
I have read on another Mazda Forum that all CX-5 NA 2.5 models from 2020 models on have had a software upgrade that allows you to monitor Cylinder Deactivation. You go to your Infotainment system, click on the far-left Applications icon and then choose the "Fuel Economy Monitor". This then brings up a drawing of your engine bay showing 4 cylinders. Four cylinders are lit up when Cylinder Deactivation is off or only the middle two cylinders are lit up indicating that Cylinder Deactivation is on. My question is this.... I have a 2018 model and some threads have suggested that in fact the 2018 do in fact have this feature. I have checked my infotainment system as mentioned above with no luck in seeing the engine bay diagram with 4 cylinders. Can anyone confirm if my 2018 NA CX-5 2.5 should have this infotainment feature, and if not, is there any software update available so I can take advantage of this feature on the monitor?
 
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18 Mazda CX5 AW
All my my so
I have read on another Mazda Forum that all CX-5 NA 2.5 models from 2020 models on have had a software upgrade that allows you to monitor Cylinder Deactivation. You go to your Infotainment system, click on the far-left Applications icon and then choose the "Fuel Economy Monitor". This then brings up a drawing of your engine bay showing 4 cylinders. Four cylinders are lit up when Cylinder Deactivation is off or only the middle two cylinders are lit up indicating that Cylinder Deactivation is on. My question is this.... I have a 2018 model and some threads have suggested that in fact the 2018 do in fact have this feature. I have checked my infotainment system as mentioned above with no luck in seeing the engine bay diagram with 4 cylinders. Can anyone confirm if my 2018 NA CX-5 2.5 should have this infotainment feature, and if not, is there any software update available so I can take advantage of this feature on the monitor?
I have read on another Mazda Forum that all CX-5 NA 2.5 models from 2020 models on have had a software upgrade that allows you to monitor Cylinder Deactivation. You go to your Infotainment system, click on the far-left Applications icon and then choose the "Fuel Economy Monitor". This then brings up a drawing of your engine bay showing 4 cylinders. Four cylinders are lit up when Cylinder Deactivation is off or only the middle two cylinders are lit up indicating that Cylinder Deactivation is on. My question is this.... I have a 2018 model and some threads have suggested that in fact the 2018 do in fact have this feature. I have checked my infotainment system as mentioned above with no luck in seeing the engine bay diagram with 4 cylinders. Can anyone confirm if my 2018 NA CX-5 2.5 should have this infotainment feature, and if not, is there any software update available so I can take advantage of this feature on the monitor?
All my software was upgraded back in May. I do not have this feature.
 

HardRightEdg

US 2020 CX-5 Touring AWD Soul Red
All my software was upgraded back in May. I do not have this feature.
If you have a real time MPG meter it will provide essentially the same info. My meter scales 0 - 80 MPG, others say theirs scales 0 - 100 MPG. I find that when the needle steadies or bobs around a bit somewhere in the 50-60 MPG range it coincides with the CD display showing 2 cylinder operation. When taking the foot off gas the needle buries at 80 MPG with the CD display showing zero cylinders operating which is just fuel injection shutting down, just what EFI does in nearly any vehicle.