Winter is here and my CX-5 turbo is now a 2.0L!

Heck, I get that kind of variance in my part of this county. So many micro-climates here. I'm 1/2 mile off of the paved road and a 75' drop in elevation.

I use a weather website called wunderground.com

People buy weather stations from Amazon, set them up, then connect to this website via the internet. It has a street-level map you zoom in/out of (can see the precipitation radar imposed right over your address). In my rural area, at one point there were easily 30 stations set up within a 10 mile radius of me. The temp variations just in that small geography were amazing.

Thats sounds really cool, Im now interested and will be checking it out. Thanks!
 
That*s exactly where I was going with questioning which sensor the computer was getting info from. I think it would be possible to test.

Here's what another member said in response to that post I quoted:

I'm sure it's a combination of the maf and 02 readings on a stock ecu. Both of my stock 02's are wired to +12v to keep the ecu from complaining since they don't do anything for me using the Haltech.

These posts are from 2008, where the OP started off with "I know that it is common knowledge about the cold weather boost cut."
 
30? It was 25 here last night, and gets in the single digits at times. Hell it's 10:15 and only 38 here right now.


Yeah, I am in Charleston and it might get down to 20 at times once or twice year but in the middle of the night. Not routine. Today it is freezing and people are all wearing winter coats and big fur lined boots. It is 52 degrees.
 
Yea, in Columbia, also known as the armpit! It*s 5-7 degrees hotter there than here just about at all times, but it too gets snow and ice and colder than 30. Come an hour and half northwest to Mountain Rest and it*s completely different. The average in January is below 30, at 28.

To say it doesn*t get any colder than 30 in SC is just plain ignorant, it*s already been colder than that a handful of time already, and today is just now Winter Solstice. Lol
Granted, he*s staying in the LowCountry, but it even snows there too. Hell it put me outta work a few years ago because the beach got more snow than the Foothills did.


Columbia is the armpit and that is saying something in a state like this! We got snow last year and had ice on the road for almost an entire week. But it would go into the 40s during the day and down to the low-20's at night - even into the teens one night! Went like that for 5 days. On certain roads, the ice would melt during the day and freeze at night. But that was maybe 7 days out of the year with temps below 30.

Speaking of Columbia, when we drive north, it can be mid 80s here, hit 102 in Columbia along they way, and be close to 70 when we hit the NC/SC border on the way to Asheville. Crazy variations in local temperature.
 
Heck, I get that kind of variance in my part of this county. So many micro-climates here. I'm 1/2 mile off of the paved road and a 75' drop in elevation.

I use a weather website called wunderground.com

People buy weather stations from Amazon, set them up, then connect to this website via the internet. It has a street-level map you zoom in/out of (can see the precipitation radar imposed right over your address). In my rural area, at one point there were easily 30 stations set up within a 10 mile radius of me. The temp variations just in that small geography were amazing.

Where I live is often a 10*F drop from where I work, due to being in a valley. Also, one part of my commute through a larger valley is a 5-8*F drop from where I live.
 
Where I live is often a 10*F drop from where I work, due to being in a valley. Also, one part of my commute through a larger valley is a 5-8*F drop from where I live.

When I had my Austin Healey, I would go driving at night all the time with the top off. I still recall this specific spot where I would hit a thermal country/city wall. The temp would drop 5* leaving the city, and would increase 5* upon the return trip...always at the same spot.
 
When I had my Austin Healey, I would go driving at night all the time with the top off. I still recall this specific spot where I would hit a thermal country/city wall. The temp would drop 5* leaving the city, and would increase 5* upon the return trip...always at the same spot.

Yup. That's how the valley I go through is.
 
I also use the Weather Underground website. I live about 4 miles from the town center but there is an 1100 ft elevation increase from the town center at 5000 ft and my home. That extra elevation can make a big difference in snowfall and temperature.
There is a map on the website showing all the weather data measuring stations in my vicinity and I picked the one that is within a quarter mile of my house.
 
More thoughts...

The engine in this vehicle produces a LOT of torque. Let's keep this in mind.

I have been reading up on this boost cut in cold weather, and WRX owners typically push around 20psi, give/take. This is due to overboost at low rpm. I have long felt that 3rd gear felt strongest in the CX5 turbo. The WRX is meant to only make 15.9psi. Overboost (WOT and low rpm causes it), is bad.

I think Mazda tuned the overboost out of the CX5. (hence why 3rd gear feels a lot stronger, and why you can feel a bit of "pick up" in the other gears near 3500 or so)

I think they then tuned out the cold weather induced overboost.

Since the engine produces a ton of torque, and car components see tq not hp, I believe that Mazda has tuned the car not to exceed 310lb-ft of torque. If you allowed it to overboost (reach normal psi, as cold weather leads to denser air), it would eclipse 310# fairly easily. I think that 20*F is just kindof the cut-off where the car says "nope! Air is too dense". and really shuts the party down, because if it didn't, wayyy too much torque would be produced. This could damage the vehicle.


None of this came from Mazda, this is just my musings over looking at the WRX owners and their cold weather boost data.
 
More thoughts...

The engine in this vehicle produces a LOT of torque. Let's keep this in mind.

I have been reading up on this boost cut in cold weather, and WRX owners typically push around 20psi, give/take. This is due to overboost at low rpm. I have long felt that 3rd gear felt strongest in the CX5 turbo. The WRX is meant to only make 15.9psi. Overboost (WOT and low rpm causes it), is bad.

I think Mazda tuned the overboost out of the CX5. (hence why 3rd gear feels a lot stronger, and why you can feel a bit of "pick up" in the other gears near 3500 or so)

I think they then tuned out the cold weather induced overboost.

Since the engine produces a ton of torque, and car components see tq not hp, I believe that Mazda has tuned the car not to exceed 310lb-ft of torque. If you allowed it to overboost (reach normal psi, as cold weather leads to denser air), it would eclipse 310# fairly easily. I think that 20*F is just kindof the cut-off where the car says "nope! Air is too dense". and really shuts the party down, because if it didn't, wayyy too much torque would be produced. This could damage the vehicle.


None of this came from Mazda, this is just my musings over looking at the WRX owners and their cold weather boost data.

I remember this being discussed (and ignored) some time ago. Can't seem to find the discussion now..

Either way, it would be nice if Mazda would confirm or deny any of these theories.
 
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I remember this being discussed (and ignored) some time ago. Can't seem to find the discussion now..

Either way, it would be nice if Mazda would confirm or deny any of these theories.
It would also be nice if they "cleaned up" the tune some in the lower temps. It doesn't have to be this radical, if indeed this is what's up. Or...maybe it does, due to the massive torque vs hp disparity of this engine?
 
I've been following this since I've been toying with the idea of downsizing from my Explorer.

Since I live in MN, below 20F is very common in winter months and I don't think I could live with 'only' N/A power. ;)

Maybe I missed it, but does anyone have any datalogs of the boost/timing/throttle position when this issue occurs?

I have a cheap Bluetooth OBD2 reader with the Torque App that I've used on my Explorer. I can see all those parameter (plus many more) real time. I believe the Torque App can also record datalogs.

I would think similar parameters could be observed with the CX5 and possibly see if there is a difference between normal and low power situations.

EDIT: I also see option to view/record mass air flow, which would be another good datapoint.
 
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More thoughts...

The engine in this vehicle produces a LOT of torque. Let's keep this in mind.

I have been reading up on this boost cut in cold weather, and WRX owners typically push around 20psi, give/take. This is due to overboost at low rpm. I have long felt that 3rd gear felt strongest in the CX5 turbo. The WRX is meant to only make 15.9psi. Overboost (WOT and low rpm causes it), is bad.

I think Mazda tuned the overboost out of the CX5. (hence why 3rd gear feels a lot stronger, and why you can feel a bit of "pick up" in the other gears near 3500 or so)

I think they then tuned out the cold weather induced overboost.

Since the engine produces a ton of torque, and car components see tq not hp, I believe that Mazda has tuned the car not to exceed 310lb-ft of torque. If you allowed it to overboost (reach normal psi, as cold weather leads to denser air), it would eclipse 310# fairly easily. I think that 20*F is just kindof the cut-off where the car says "nope! Air is too dense". and really shuts the party down, because if it didn't, wayyy too much torque would be produced. This could damage the vehicle.


None of this came from Mazda, this is just my musings over looking at the WRX owners and their cold weather boost data.
The boost pressure is controlled by an internal wastegate which effectively lets the exhaust turbine be bypassed before compressor turbine air gets sent on through quite a large air to air intercooler. The intercooler is the part that sits down by the radiator to cool the incoming charge air. The valve that bypasses the turbine is going like a fiddlers elbow all day every day even in summer. If they needed to regulate the power, why don’t they regulate it at 300 ft/lbs instead of this noticeable lower amount? They don’t regulate the diesel in this way. I leave my town up a steep hill on a road where I can get up to 70 mph quite easily. The car isn’t flat out by any means but it’s about the limit of negotiating the bends safely. It doesn’t get to that speed any noticeable difference in summer or sub zero temps. Why should they impose or struggle with power regulation on the G engine when they are perfectly capable of producing consistent output on the D engine. I’m not attacking your theory, only posing the question.
 

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  • Wastegate.pdf
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It has another regulating valve on the intake impeller.
 

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  • Air Bypass valve.pdf
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More thoughts...

The engine in this vehicle produces a LOT of torque. Let's keep this in mind.

I have been reading up on this boost cut in cold weather, and WRX owners typically push around 20psi, give/take. This is due to overboost at low rpm. I have long felt that 3rd gear felt strongest in the CX5 turbo.

I agree with this. I drive in manual mode all the time, and 3rd gear pushes me back in the seat unlike any other gear.
 
I've been following this since I've been toying with the idea of downsizing from my Explorer.

Since I live in MN, below 20F is very common in winter months and I don't think I could live with 'only' N/A power. ;)

Maybe I missed it, but does anyone have any datalogs of the boost/timing/throttle position when this issue occurs?

I have a cheap Bluetooth OBD2 reader with the Torque App that I've used on my Explorer. I can see all those parameter (plus many more) real time. I believe the Torque App can also record datalogs.

I would think similar parameters could be observed with the CX5 and possibly see if there is a difference between normal and low power situations.

EDIT: I also see option to view/record mass air flow, which would be another good datapoint.
I have an OBD2 reader and both ScanTool and TorquePro installed. I don't believe the offering of late model Mazda PIDs is that deep yet. I've been waiting for ScanTool to offer their $10 PID set for the 2019 model year, but they're not developed yet. I've found that the standard PID set is extremely limited.
 
It would also be nice if they "cleaned up" the tune some in the lower temps. It doesn't have to be this radical, if indeed this is what's up. Or...maybe it does, due to the massive torque vs hp disparity of this engine?

I agree with "clean up" the tune. With all this modern tech, you'd think they could program it to maintain the same torque, regardless of ambient temperature or pressure and not 'castrate' it when temps go down.
 
From a practical standpoint, does the power reduction impact driving much at those lower temps? I live in the Far North and drive on snow/ice at least five months of the year. I put studded tires on in Nov and leave them on until March. So far this January we haven’t seen temps above 10F. I am driving a little Buick sedan with the 2L turbo (rated 250hp/250tq) but never really put my foot in it this time of year anyways. Just wondering....

I am looking to replace my 2010 Toyota RAV4 V-6 AWD Sport with another compact SUV and the CX5 GTR/Sig is at the top of my list.
 
From a practical standpoint, does the power reduction impact driving much at those lower temps? I live in the Far North and drive on snow/ice at least five months of the year. I put studded tires on in Nov and leave them on until March. So far this January we haven’t seen temps above 10F. I am driving a little Buick sedan with the 2L turbo (rated 250hp/250tq) but never really put my foot in it this time of year anyways. Just wondering....

I am looking to replace my 2010 Toyota RAV4 V-6 AWD Sport with another compact SUV and the CX5 GTR/Sig is at the top of my list.

I don't think it would be a concern for you, given your environment. I live in similar conditions and I never feel like I'm lacking power in my CX-9, BUT I also do mostly city driving and rarely need to drive on the highway/merge onto a highway. If you feel that you need 100% of the power while driving on roads that are below freezing temps, this may not be the car for you (but I would test drive it anyway to see if it exhibits the same behavior as the OP). But based on the bolded statement above, you're not likely to notice any difference.
 
0*F on the drive home tonight. Same loss in every gear from what I can tell. Pulls normal from 2k-2,500 then just falls flat. Such a disappointment.
 
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