Disable Cylinder Deactivation

I think 2001Snow is feeling something other than the CD transition. The engine has no load on it when it transitions thus no ability to create a jolt, unless like other said, his car has a defect. Maybe one of the rocker arms fell off. A rocker arm getting caught in the cam would cause a jolt.
 
... Maybe one of the rocker arms fell off. A rocker arm getting caught in the cam would cause a jolt.
Yes, I also had considered the detached rocker arm as a possibility for what the OP of this thread is reporting. However, the big CD thread started by Go Hawks would lead one to believe that a displaced arm would result in limp mode (or worse), anytime the vehicle is pushed hard. But OTOH I guess it can't be ruled out either.

Given that this OP is so upset by what his CX-5 is doing, perhaps he might want to snake an inspection camera in to inspect the arms, as described by Luke_M6 in that same big thread. Or perhaps he's so pi$$ed off by now because no one is taking his side, that we'll never be hearing from him again ;)
 
Calling it a mild jolt is definitely exaggerated but the transition is noticeable to me. And I should clarify, I do not notice every time it switches to 2 cylinders. Mostly under 50 mph with the RPMs close to 2k.

I’m not saying or thinking it’s a problem, just annoying.

It’s not uncommon for people to complain about vibrations in general from CD engines. This includes complaints from Cx-30 and Mazda3 owners with the same engine. Honda owners have also complained about one of the V6s with CD.
 
I detect nothing I would characterize as a vibration in this vehicle under any conditions except one: the steering wheel vibration when the lane keeping assist engages.
 
i have similar issue on my mazda 6 2018.
i can clearly feel vibration when running on 2 cylinders. also i can feel slight jolt when switching between 2 and 4 cylinders.
other thing that are annoying - torque converter lock up - every other lockup on lower gears is a noticeable jolt.

also annoying that i cannot disable CD, torque converter lockup, and i-eloop (recuperation).
 
i have similar issue on my mazda 6 2018.
i can clearly feel vibration when running on 2 cylinders. also i can feel slight jolt when switching between 2 and 4 cylinders.
other thing that are annoying - torque converter lock up - every other lockup on lower gears is a noticeable jolt.

also annoying that i cannot disable CD, torque converter lockup, and i-eloop (recuperation).

The tsb for the Mazda3 and cx-30 states the vibration under 2k is “normal”. However , there is a PCM update and new radiator brackets that are supposed to improve it.

Idk how a straight 4 running on 2 cylinders at 1500 rpm wouldn’t cause vibrations. It really is a stupid thing Mazda did here. I doubt it will be in the 22s.
 
The tsb for the Mazda3 and cx-30 states the vibration under 2k is “normal”. However , there is a PCM update and new radiator brackets that are supposed to improve it.

Idk how a straight 4 running on 2 cylinders at 1500 rpm wouldn’t cause vibrations. It really is a stupid thing Mazda did here. I doubt it will be in the 22s.

Oddly enough, in the TSB they state that the new brackets may also cause the vibrations to get worse, and state that it is normal. :unsure:
 
Oddly enough, in the TSB they state that the new brackets may also cause the vibrations to get worse, and state that it is normal. :unsure:
Yeah it’s kind of a worthless TSB. But it does confirm Mazda acknowledges the vibrations below 2k rpm when running on 2 cylinders.
 
I think 2001Snow is feeling something other than the CD transition. The engine has no load on it when it transitions thus no ability to create a jolt, unless like other said, his car has a defect. Maybe one of the rocker arms fell off. A rocker arm getting caught in the cam would cause a jolt.
Being sure the engine control software update recall related to the rocker arm issue has been applied would be a first step.

Other than that, I tend to agree with what you say as the 2020 CX-5 2.5L is concerned. What might be happening in another model or year is something else entirely which I could not comment on.

As I commented in other threads already, this vehicle will lug or jolt a bit getting from first gear to second or second to third in normal (not sport) mode if you're light on the gas pedal or you don't work the gas in line with what it wants for it's torque curve and gearing. I experienced this in two different test drives with two different 2020 2.5L vehicles at different dealers a couple months apart, one new and then the dealer loaner I bought. So, I chalk it up to the character of the vehicle.

Now, if somebody characterized what I call a low gear "lug" as a vibration, so be it. "Vibration" is kind of vague. And accelerating out of a lug just might get you a bit of a jolt. But I believe that's more a function of torque curve and gear ratios than cylinder deactivation. More vroom-vroom on the giddy-up pretty much solves the problem.

There's one spot I drive frequently with a super tight, 180 degree hairpin turn with on-coming traffic. It lugs every time accelerating out of that turn and I don't think there's any way around it without pushing to handling limits, not something I care to do in routine driving. It occurs to me this would not be a good vehicle for urban driving with stoplights ever 1/10 - 1/4 mile since you can only gas it as hard as the guy in front of you. I live in exurbia so no worries here.

One way to get rid of this lug/jolt is use the sport mode, but I found it a bit wonky in normal driving. I found settling in behind a guy doing 45 mph had the thing revving at 3000 RPMs waiting for more gas to upshift.

I did quite a bit of testing with the cylinder deactivation display at low and highway speeds shortly after purchase, monitoring when CD would kick on and off at a variety of speeds. Frankly, I found the transitions to be seamless.
 
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Being sure the engine control software update recall related to the rocker arm issue has been applied would be a first step.

Other than that, I tend to agree with what you say as the 2020 CX-5 2.5L is concerned. What might be happening in another model or year is something else entirely which I could not comment on.

As I commented in other threads already, this vehicle will lug or jolt a bit getting from first gear to second or second to third in normal (not sport) mode if you're light on the gas pedal or you don't work the gas in line with what it wants for it's torque curve and gearing. I experienced this in two different test drives with two different 2020 2.5L vehicles at different dealers a couple months apart, one new and then the dealer loaner I bought. So, I chalk it up to the character of the vehicle.

Now, if somebody characterized what I call a low gear "lug" as a vibration, so be it. "Vibration" is kind of vague. And accelerating out of a lug just might get you a bit of a jolt. But I believe that's more a function of torque curve and gear ratios than cylinder deactivation. More vroom-vroom on the giddy-up pretty much solves the problem.

There's one spot I drive frequently with a super tight, 180 degree hairpin turn with on-coming traffic. It lugs every time accelerating out of that turn and I don't think there's any way around it without pushing to handling limits, not something I care to do in routine driving. It occurs to me this would not be a good vehicle for urban driving with stoplights ever 1/10 - 1/4 mile since you can only gas it as hard as the guy in front of you. I live in exurbia so no worries here.

One way to get rid of this lug/jolt is use the sport mode, but I found it a bit wonky in normal driving. I found settling in behind a guy doing 45 mph had the thing revving at 3000 RPMs waiting for more gas to upshift.

I did quite a bit of testing with the cylinder deactivation display at low and highway speeds shortly after purchase, monitoring when CD would kick on and off at a variety of speeds. Frankly, I found the transitions to be seamless.

For me it’s a number of conditions happening at the same time that make the 4 to 2 transition noticeable. Just so happens that a route I drive regularly includes all these conditions.

Light throttle (barely on the pedal)
Light load (minor incline or just flat)
RPMs below 2k (Under 50 mph)

If those conditions aren’t there, I don’t notice the transition from 4 to 2.

The vibration once running on 2 cylinders is really only noticeable below 2k as well.
 
For me it’s a number of conditions happening at the same time that make the 4 to 2 transition noticeable. Just so happens that a route I drive regularly includes all these conditions.

Light throttle (barely on the pedal)
Light load (minor incline or just flat)
RPMs below 2k (Under 50 mph)

If those conditions aren’t there, I don’t notice the transition from 4 to 2.

The vibration once running on 2 cylinders is really only noticeable below 2k as well.
I know those conditions. My hairpin turn example fits. Earlier I cited an example of coming up an incline into a 90 degree left turn at a T intersection where the cross traffic has stop signs but I do not. It's dangerous because sometimes cross traffic drivers assume I have a stop sign so I slow way down to watch for a stopped car failing to yield right of way.

The vehicle lugs under these conditions and I wonder if that's what you are calling a "vibration" under lower speed conditions. That lug is the same thing you'd feel in a manual transmission when your RPMs drop too low and the load too high for the gear you're in.

Like I said, I chalk it up to the torque/gearing set up rather than cylinder deactivation. You've got a 187 hp / 4 cylinder / 6 speed in a vehicle weighing 4,600 to 4,800 lbs. It's kind of hard to get flawless shifting under all conditions with that set up. I don't think you'll find a vehicle on the road with that configuration that doesn't give you a lug or a gear hunt under specific circumstances. I cannot account for the folks that sense a vibration at 50 mph because I've never felt that.

Now, if the torque/gearing setup is because of cylinder deactivation, or because they've added the manual shifter, or because they are encouraging vroom-vroom at the get-off, then we're talking chickens vs. eggs, more of a wholistic thing where tweaking one thing affects something else. In another thread about the 2018 somebody attributed this lug to the torque converter, so toss that into the wholistic mix.

I look on the bright side. The quiet and comfortable ride that is well composed over bumps (on the 17" wheels anyway) while having muted body roll in an aggressive turn despite the high center of gravity in a CUV is kind of a minor miracle. I also find the motor gives off a pleasant growl when you put the pedal down. I'll take the occasional lug in exchange.
The tsb for the Mazda3 and cx-30 states the vibration under 2k is “normal”. However , there is a PCM update and new radiator brackets that are supposed to improve it.

Idk how a straight 4 running on 2 cylinders at 1500 rpm wouldn’t cause vibrations. It really is a stupid thing Mazda did here. I doubt it will be in the 22s.
Cylinder deactivation is for some minor improvement in mpgs, and still the rating is at the low end of the competition with their little turbos and CVTs. I don't think they'll just drop CD without going to a whole different configuration, a small block turbo like the Honda or a CVT like the Toyota, setups that have their own issues.

Mazda entered into a joint venture with Toyota, sharing a plant, for what specifically I have not seen:


I joked (kinda) that Mazda will come out with a crossover with a Toyota hybrid drive train. Stiffer fuel economy standards are on the way. It's going to be very hard to build cars if you can't move some significant product with high MPGs, hybrids and/or electrics, to get the fleet above standard.
 
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I know those conditions. My hairpin turn example fits. Earlier I cited an example of coming up an incline into a 90 degree left turn at a T intersection where the cross traffic has stop signs but I do not. It's dangerous because sometimes cross traffic drivers assume I have a stop sign so I slow way down to watch for a stopped car failing to yield right of way.

The vehicle lugs under these conditions and I wonder if that's what you are calling a "vibration" under lower speed conditions. That lug is the same thing you'd feel in a manual transmission when your RPMs drop too low and the load too high for the gear you're in.

Like I said, I chalk it up to the torque/gearing set up rather than cylinder deactivation. You've got a 187 hp / 4 cylinder / 6 speed in a vehicle weighing 4,600 to 4,800 lbs. It's kind of hard to get flawless shifting under all conditions with that set up. I don't think you'll find a vehicle on the road with that configuration that doesn't give you a lug or a gear hunt under specific circumstances. I cannot account for the folks that sense a vibration at 50 mph because I've never felt that.

Now, if the torque/gearing setup is because of cylinder deactivation, or because they've added the manual shifter, or because they are encouraging vroom-vroom at the get-off, then we're talking chickens vs. eggs, more of a wholistic thing where tweaking one thing affects something else. In another thread about the 2018 somebody attributed this lug to the torque converter, so toss that into the wholistic mix.

I look on the bright side. The quiet and comfortable ride that is well composed over bumps (on the 17" wheels anyway) while having muted body roll in an aggressive turn despite the high center of gravity in a CUV is kind of a minor miracle. I also find the motor gives off a pleasant growl when you put the pedal down. I'll take the occasional lug in exchange.

Cylinder deactivation is for some minor improvement in mpgs, and still the rating is at the low end of the competition with their little turbos and CVTs. I don't think they'll just drop CD without going to a whole different configuration, a small block turbo like the Honda or a CVT like the Toyota, setups that have their own issues.

Mazda entered into a joint venture with Toyota, sharing a plant, for what specifically I have not seen:


I joked (kinda) that Mazda will come out with a crossover with a Toyota hybrid drive train. Stiffer fuel economy standards are on the way. It's going to be very hard to build cars if you can't move some significant product with high MPGs, hybrids and/or electrics, to get the fleet above standard.

What your describing sounds like it’s just in too high a gear for your liking, which is understandable.

The vibration I’m referring to is 100% caused by running on 2 cylinders. A minor increase in throttle and it smooths out without downshifting. The fuel economy display changes from 2 to 4 cylinders when this happens. It’s subtle but I can feel it.

Most of the time I find the throttle response and shifting to be consistent and predictable.

Also, what MyFirstMazda said about no load when CD activates is not true. There has to be some load and throttle input for it to activate. As soon as you get off the throttle CD is deactivated, when you get back on the gas, all 4 cylinders are firing until it determines in can activate again. There is a graph from Mazda floating around that confirms this.

And I agree that the overall driving experience makes up for some of the quirks. I’m not happy about the CD but I’d still choose the Cx-5 over the competitors in the class.
 
It’s likely your driving styles or you just don’t notice it because you’re not as in tune with your cars as I am. That’s not at all meant to be offensive I’m really sensitive to things like this.

My wife has no idea it’s happening. Her driving style also includes constantly being on and off the gas, which means CD in’t kicking in as much.

If you’re cruising at around 1500 RPMs with your foot steady on the gas and light load (minor incline) it’s impossible to not notice.
I was out and about today and did a retest. Yes, easing off the gas at 50 mph with the cylinder monitor showing it kicked down to 2 cylinders running around 1750 rpm I could feel an ever so slight vibration in the steering wheel and an ever so light change in engine tone. Also at 60 mph.

Here's the thing--that was on a very flat, smooth blacktop just paved this past fall. The sensation is so slight that on other stretches of pavement with some combination of rough surface, filled cracks and/or a slight bit of pavement chop/bounce (like most roads I drive) the CD switch to 2 cylinders was not distinguishable from the vibration set up from the tires through the suspension to the cabin from the road imperfections. I'm talking very slight here.

I gotta say this is a nothing burger. If you feel something more pronounced that's something else that might need to be checked out.
 
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So apparently there's no way to totally disable CD. Saw a recent video related to this...though with the Honda, not sure if it's pretty much the same with the CX-5:
 
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