CX-5 Cylinder deactivation

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Has anyone road tested the 2018 CX-5 yet? I'm curious to see, if Mazda was able to push more performance and offset the loss of MPG with cylinder deactivation.

Well I am just about to hit 1000 km (955 km on odometer) on my '18 and it is pure City driving, no highway yet and my avg. consumption right now since I started driving this is around 10.4L/100km which is 22.61679 mpg (by google conversion) close to that chart above. I am hoping that this is going to change after 1000 km because I will be going on a highway very soon.

I not sure if heating up the engine for 15 mins (remote starter from dealer) would add to that reader. Someone could verify this?
 
Well I am just about to hit 1000 km (955 km on odometer) on my '18 and it is pure City driving, no highway yet and my avg. consumption right now since I started driving this is around 10.4L/100km which is 23.5215 mpg (by google conversion). I am hoping that this is going to change after 1000 km because I will be going on a highway very soon.

I not sure if heating up the engine for 15 mins (remote starter from dealer) would add to that reader. Someone could verify this?

Yes, leaving the engine just sitting there idling for 15 min will definitely impact gas mileage. Just think, for 15 min the car is getting 0mpg. You can see this if you turn on the option to have the gas mileage displayed on the infotainment screen every time you turn off your car. If you just sit there and let it run, than turn the car off, it will read 0mpg for that trip.
 
Well I am just about to hit 1000 km (955 km on odometer) on my '18 and it is pure City driving, no highway yet and my avg. consumption right now since I started driving this is around 10.4L/100km which is 22.61679 mpg (by google conversion) close to that chart above. I am hoping that this is going to change after 1000 km because I will be going on a highway very soon.

I not sure if heating up the engine for 15 mins (remote starter from dealer) would add to that reader. Someone could verify this?
22 mpg in pure city driving is not surprising.

Unless you really need to, don't let it idle for 15 minutes just to warm it up in cold weather. You are doing more damage to the engine than just turning it on and driving off right away.
 
Has anyone road tested the 2018 CX-5 yet? I'm curious to see, if Mazda was able to push more performance and offset the loss of MPG with cylinder deactivation.

The specs on the engine (HP and Torque) are the same. So i don't expect any change in performance.

I drove both a 17 and 18 before buying the 18. I saw no difference. Unless you look for the few interior changes (vent off/on wheels and lighted window buttons) you would not know you were driving an 18.
 
The specs on the engine (HP and Torque) are the same. So i don't expect any change in performance.

I drove both a 17 and 18 before buying the 18. I saw no difference. Unless you look for the few interior changes (vent off/on wheels and lighted window buttons) you would not know you were driving an 18.

Does the 2018 car weigh the same?
 
The specs on the engine (HP and Torque) are the same. So i don't expect any change in performance.

I drove both a 17 and 18 before buying the 18. I saw no difference. Unless you look for the few interior changes (vent off/on wheels and lighted window buttons) you would not know you were driving an 18.

If that is the case and pending performance test results from car mags, looks like the inclusion of cylinder deactivation was just a way to prevent losing even more MPG. This allows Mazda to stuff more tech and features to the CX-5 (making it heavier) and offset the loss to MPG with cylinder deactivation. Of course everything I'm saying is purely speculation though it makes sense to me.
 
not that I think this thing is a good idea, but anyone consider that the past issues with owners of other brands just used the cheapest crappiest oil or neglected to follow maintenance schedules?
In the US, you can get god awful motor oils that still manages to pass API specs, while failing to meet manufacturer specs, ILSAC ratings, ACEA specs, etc

good oils are more expensive and your typical car owner won't know or care about the differences, and even of those which buy into synthetic oil upsells, they won't know the differences between the different brands too... thus, they get conned by the shop and the shop uses the cheapest synthetic oil they can get that fails to meet manufacturer specs

in Europe and Japan, this is less of an issue as high quality oils along with higher price tags are the norm
 
Even more sound proofing? An extra 36-38 pounds of what?

I believe you are getting more standard features such as memory seats and a few other things may contribute to some increase in weight but doesn't explain all of it.

Cylinder deactivation shouldn't add that much. Maybe it is more sound proofing.
 
There was lots of talk of balance shafts, special pistons and engine mounts but the only difference is with a glorified thermostat called a coolant control valve which might make a slight difference to the coolant capacity and the hydraulic lash adjuster that deactivates the compression in the cylinder. Everything else is identical to the current 2.5G. Ive spent quite a lot of time on the Mazda website today reading about it. It seems that its a simple as letting cylinders 1 and 4 run light. Theres no fuel and no spark but enough compression to stop oil ingress problems.

Ive got quite a few new PDFs but these explains the process and the hydraulic lash adjuster.
 
There was lots of talk of balance shafts, special pistons and engine mounts but the only difference is with a glorified thermostat called a coolant control valve which might make a slight difference to the coolant capacity and the hydraulic lash adjuster that deactivates the compression in the cylinder. Everything else is identical to the current 2.5G. I’ve spent quite a lot of time on the Mazda website today reading about it. It seems that it’s a simple as letting cylinders 1 and 4 run light. There’s no fuel and no spark but enough compression to stop oil ingress problems.

I’ve got quite a few new PDFs but these explains the process and the hydraulic lash adjuster.

(hmm) interesting.....

So no sludging issue(s) (uhm)
 
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There was lots of talk of balance shafts, special pistons and engine mounts but the only difference is with a glorified thermostat called a coolant control valve which might make a slight difference to the coolant capacity and the hydraulic lash adjuster that deactivates the compression in the cylinder. Everything else is identical to the current 2.5G. I’ve spent quite a lot of time on the Mazda website today reading about it. It seems that it’s a simple as letting cylinders 1 and 4 run light. There’s no fuel and no spark but enough compression to stop oil ingress problems.

I’ve got quite a few new PDFs but these explains the process and the hydraulic lash adjuster.

Thank you very much for PDFs! Yes, Mazda is doing this the same way as the other OEMs, nothing is different here. Unless they use special oil manifold for lash adjusters control like VLOM in GM engines, the head will be different to allow for additional control oil passages and valves.
I can't see how they mitigate the factors that make such systems a fiasco at other OEMs though. If they found a compromise that allows for the actual fuel savings and acceptable longevity, that is incredible.

By the way, I'm not sure I understand what do you mean by this:
... hydraulic lash adjuster that deactivates the compression in the cylinder.

And that:
It seems that it’s a simple as letting cylinders 1 and 4 run light.
 
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There was lots of talk of balance shafts, special pistons and engine mounts but the only difference is with a glorified thermostat called a coolant control valve which might make a slight difference to the coolant capacity and the hydraulic lash adjuster that deactivates the compression in the cylinder. Everything else is identical to the current 2.5G. I’ve spent quite a lot of time on the Mazda website today reading about it. It seems that it’s a simple as letting cylinders 1 and 4 run light. There’s no fuel and no spark but enough compression to stop oil ingress problems.

I’ve got quite a few new PDFs but these explains the process and the hydraulic lash adjuster.

Other than the particulars of how they disable value operation, it looks like every other cylinder deactivation system to me. What's different?
 
Thank you very much for PDFs! Yes, Mazda is doing this the same way as the other OEMs, nothing is different here. Unless they use special oil manifold for lash adjusters control like VLOM in GM engines, the head will be different to allow for additional control oil passages and valves.
I can't see how they mitigate the factors that make such systems a fiasco at other OEMs though. If they found a compromise that allows for the actual fuel savings and acceptable longevity, that is incredible.

By the way, I'm not sure I understand what do you mean by this:


And that:
Other than the particulars of how they disable value operation, it looks like every other cylinder deactivation system to me. What's different?
I agree with both of you and we still haven't seen anything special from Mazda to prevent common issues from cylinder deactivation. This makes me worried for Mazda a few years later when CX-5 owners are running into the exact same problems like every other vehicles with cylinder deactivation! Mazda may program its system activated less frequently with very short cycle, but thiss a 4 cylinder which could make the common symptoms showing up faster than those V6s and V8s!
 
I agree with both of you and we still haven't seen anything special from Mazda to prevent common issues from cylinder deactivation. This makes me worried for Mazda a few years later when CX-5 owners are running into the exact same problems like every other vehicles with cylinder deactivation! Mazda may program its system activated less frequently with very short cycle, but thiss a 4 cylinder which could make the common symptoms showing up faster than those V6s and V8s!

I would think the opposite would be true.
The only place the cylinder deactivation will actually get used is on the EPA test cycle.
 
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