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

Even at 40-80 you’ll feel the boost but the boost is not 100%. I feel like it’s prob 50% or lower.
0-40, absolutely zero boost. It’s even slower than a non turbo cx5. When I took my cx5 in to dealer to complain about the power loss, I had a loaner cx5 non turbo and it never had any power loss at lower temps. It even picks up quicker than the turbo cx5 at lower temps.

This kind of reaffirms (at least for me) that the cut is some form of engine protection in the form of overboost prevention.
 
This kind of reaffirms (at least for me) that the cut is some form of engine protection in the form of overboost prevention.
Would be interesting to know if this is just a Mazda thing, or if all turbo engine manufacturers do this.
Never having owned a turbo equipped vehicle, I'm curious to know if others do this....before I trade in any of my vehicles and buy a turbo equipped car.
 
Would be interesting to know if this is just a Mazda thing, or if all turbo engine manufacturers do this.
Never having owned a turbo equipped vehicle, I'm curious to know if others do this....before I trade in any of my vehicles and buy a turbo equipped car.

I think I read here that someone mentioned this quirk existing on certain turbocharged Subaru cars, with the difference being that Subaru did confirm it was to prevent overboost. Subaru may have been more forthcoming with the info as they have a huge enthusiast/tuner base. I suspect that Uno is right in guessing that it has something to do with the dynamic pressure turbo.
 
I think I read here that someone mentioned this quirk existing on certain turbocharged Subaru cars, with the difference being that Subaru did confirm it was to prevent overboost. Subaru may have been more forthcoming with the info as they have a huge enthusiast/tuner base. I suspect that Uno is right in guessing that it has something to do with the dynamic pressure turbo.
My wife’s 19’ Ascent seems to have a a bit of turbo cut off but it’s not as significant as the CX-5. Also, after 10minutes of driving with the ascent, all power returns. Where as the cx5’s power never returns.

Again my cx5, between 10-25 degrees, you’ll have to drive the car for at least 30 minutes, turn off your vehicle and turn it back on for the turbo to return.

Under 10 degrees, after driving for over 30 minutes, turn off vehicle and turn it back on, I still have zero turbo.
Might be a sensor that “protects” turbo. But I find it very annoying and frustrating.
 
My wife’s 19’ Ascent seems to have a a bit of turbo cut off but it’s not as significant as the CX-5. Also, after 10minutes of driving with the ascent, all power returns. Where as the cx5’s power never returns.

Again my cx5, between 10-25 degrees, you’ll have to drive the car for at least 30 minutes, turn off your vehicle and turn it back on for the turbo to return.

Under 10 degrees, after driving for over 30 minutes, turn off vehicle and turn it back on, I still have zero turbo.
Might be a sensor that “protects” turbo. But I find it very annoying and frustrating.

I was referring mostly to the Impreza, but interesting that it happens to the Ascent as well. I have a CX-9 and its the same. There is a slightly noticeable difference, but nowhere near as noticeable as what others have described in the CX-5. I can't even tell there's a difference in my driving, and that includes a couple of sprints from 60-90km/hr (40-55mph), but that may be because of my driving style, the fact that the CX-9 is heavier, the transmission is tuned differently, or some other combination of factors.
 
I was referring mostly to the Impreza, but interesting that it happens to the Ascent as well. I have a CX-9 and its the same. There is a slightly noticeable difference, but nowhere near as noticeable as what others have described in the CX-5. I can't even tell there's a difference in my driving, and that includes a couple of sprints from 60-90km/hr (40-55mph), but that may be because of my driving style, the fact that the CX-9 is heavier, the transmission is tuned differently, or some other combination of factors.
When it’s super cold you’ll notice it on the Ascent, cold as in below zero. Otherwise the Ascent runs like a champ with its turbo.
Interesting that your cx9 does not lose power. It’s the same engine. And yeah maybe tuned differently. I don’t understand why the cx5 loses its turbo completely and you need to literally turn vehicle off and turn it back on to get the turbo after driving it for a while. Also in negative temps, you just don’t get it at all.
 
When it’s super cold you’ll notice it on the Ascent, cold as in below zero. Otherwise the Ascent runs like a champ with its turbo.
Interesting that your cx9 does not lose power. It’s the same engine. And yeah maybe tuned differently. I don’t understand why the cx5 loses its turbo completely and you need to literally turn vehicle off and turn it back on to get the turbo after driving it for a while. Also in negative temps, you just don’t get it at all.

To clarify, my CX-9 does lose power, I just don't notice it in my daily driving. As Uno mentioned earlier, it is most noticeable in early gears at WOT. I did a 0-60 comparison last year - when temps were warm (25-30F) I logged a time of 7.8s. When they were at about 16F I logged a time of 9.0s. By comparison, 2.5T CX-5s have a 0-60 of about 6.4s, and Uno was logging times well above that.

To add to the confusion, a Mazda6 2.5T owner stated that he didn't feel there was any power loss below 20F.

Some interesting info from @Jeff F, who stated that he is an automotive engineer that has worked at OEs and done calibration work on turbo engines. And an offer to provide some technical assistance for anyone willing to do more involved testing.
 
To clarify, my CX-9 does lose power, I just don't notice it in my daily driving. As Uno mentioned earlier, it is most noticeable in early gears at WOT. I did a 0-60 comparison last year - when temps were warm (25-30F) I logged a time of 7.8s. When they were at about 16F I logged a time of 9.0s. By comparison, 2.5T CX-5s have a 0-60 of about 6.4s, and Uno was logging times well above that.

To add to the confusion, a Mazda6 2.5T owner stated that he didn't feel there was any power loss below 20F.

Some interesting info from @Jeff F, who stated that he is an automotive engineer that has worked at OEs and done calibration work on turbo engines. And an offer to provide some technical assistance for anyone willing to do more involved testing.
That is frustrating to hear that a mazda6 w/turbo has no power loss.
Yeah I wouldn’t mind doing any testing. Got any more info on that?
 
That is frustrating to hear that a mazda6 w/turbo has no power loss.
Yeah I wouldn’t mind doing any testing. Got any more info on that?

Please refer to the post by @Jeff F that I linked. He would be the one to talk to.
 
Test drove 2021 cx-5 signature and cx-9 gt Friday when it was 18 before the weather warmed up. I ran out of time to drive a non turbo for direct comparison. I didn't figure much out by feel. Both had under 10 miles on them so didn't feel right doing WOT runs in them. Acceleration seemed decent but not what I hoped for. Whether to keep them on my list is still up in the air.
 
Acceleration in normal weather is plenty fine. Yesterday for example I killed a 2015 Camaro RS from a freeway punch. These cars are quite fine in normal conditions.
 
Acceleration in normal weather is plenty fine. Yesterday for example I killed a 2015 Camaro RS from a freeway punch. These cars are quite fine in normal conditions.
I get the majority of time it's fine. But here in Minnesota morning temps are below 20F as early as late October to end of March. And daytime highs 20 or less are fairly common late November into February.

Does parking in a garage help with morning temps? It's not heated but partially insulated so it stays warm enough so pop doesn't freeze unless it's below zero outside for long stretches
 
I just rented a Vanderhall Venice, 2 days ago. It has a 1.8 liter turbocharged 4 banger with 180 HP. Fortunately, the car-cycle (it has 3 wheels) weighs only 1400 lbs or so. I wish I could see the looks on the faces of some of the vehicle owners who thought the car was a home made one with a wimpy engine. 0-60 MPH is sub 5 seconds. I did have to turn on its heated seats after 6:00 PM, as temps dipped into the upper 50s.
 
Wow, I'm really glad I found this thread! I've recently noticed this issue when temps fall below around -5c here in Ontario, Canada. At first I thought it might be a traction control issue but quickly ruled that out. After a bit more testing I started noticing that power returned after 3rd gear; the issue seemed mostly limited to 1st and 2nd. The acceleration difference is drastically different and has caught me out a few times when needing to quickly pull out into busy traffic. In my opinion, this is actually a little bit dangerous, as the difference in acceleration isn't minor. You become used to how a car drives and when it unexpectedly doesn't perform or behave how it should, it can be a little frustrating. Canada is cold in the winter. I typically run 94oct, so I expect at or near 250hp, even in the cold.

I have owned two Subaru WRX STis, both tuned by me, and currently driving my wife's old '09 WRX (waiting for the next STI). None of those cars exhibited this issue in the winter, stock or modded. I understand the argument that the ECU tune on the CX-5 turbo is likely attempting to prevent over-boost or protect the engine in some way. The turbo Subarus have a similar feature in the ECU maps called Wastegate Duty Cycle Intake Air Temperature Compensation (or something like iirc). So as the air temp drops, the duty cycle is lowered, allowing more bleed off of exhaust energy. This helps prevent over-boosting when the air is more dense. Now, with that said, even though the boost target and WGDC are lower, the Subarus still drive as expected. My wife's '09 WRX pulls just as hard in 1st and 2nd whether it is summer or winter. The CX-5, not so much.

Mazda should really sort this out or release a technical service bulletin about it. I don't know if it is due to DPT and/or DI, but given the drastic difference in power and the fact that there is no official notice or warning anywhere about this could get Mazda into some hot water if someone were to press the issue. We're not talking a 10-15hp drop - I swear when this issue occurs, the car isn't making much more than 160-170hp, until 3rd kicks in and then it's mostly back to normal.

Thankfully, it's my wife's car and mainly meant to be a fun commuter and travel vehicle. I still love almost everything about it, the fit & finish, the driving feel, and the acceleration ... when it isn't being limited.

I'm glad this thread exists though, as I truly thought I was going nuts or that there was something wrong with the vehicle. :)

Edit:

The really odd thing about this issue is how abrupt the changeover point is. It certainly doesn't feel like the ECU progressively pulls boost (and timing) as the temps lower. The boost-cut seems to occur at a very well-defined air temperature - almost like an all or nothing situation. Now maybe the tables for target boost and IAT compensation don't have a lot of resolution, so the steps between air temp ranges are relatively abrupt...who knows. But it sucks whatever the reason. :)
 
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I just rented a Vanderhall Venice, 2 days ago. It has a 1.8 liter turbocharged 4 banger with 180 HP. Fortunately, the car-cycle (it has 3 wheels) weighs only 1400 lbs or so. I wish I could see the looks on the faces of some of the vehicle owners who thought the car was a home made one with a wimpy engine. 0-60 MPH is sub 5 seconds. I did have to turn on its heated seats after 6:00 PM, as temps dipped into the upper 50s.

Nice, but this doesn't seem to relate to the topic at hand unless it experiences the same boost cut that the CX-5 turbo does.
 
Wow, I'm really glad I found this thread! I've recently noticed this issue when temps fall below around -5c here in Ontario, Canada. At first I thought it might be a traction control issue but quickly ruled that out. After a bit more testing I started noticing that power returned after 3rd gear; the issue seemed mostly limited to 1st and 2nd. The acceleration difference is drastically different and has caught me out a few times when needing to quickly pull out into busy traffic. In my opinion, this is actually a little bit dangerous, as the difference in acceleration isn't minor. You become used to how a car drives and when it unexpectedly doesn't perform or behave how it should, it can be a little frustrating. Canada is cold in the winter. I typically run 94oct, so I expect at or near 250hp, even in the cold.

I have owned two Subaru WRX STis, both tuned by me, and currently driving my wife's old '09 WRX (waiting for the next STI). None of those cars exhibited this issue in the winter, stock or modded. I understand the argument that the ECU tune on the CX-5 turbo is likely attempting to prevent over-boost or protect the engine in some way. The turbo Subarus have a similar feature in the ECU maps called Wastegate Duty Cycle Intake Air Temperature Compensation (or something like iirc). So as the air temp drops, the duty cycle is lowered, allowing more bleed off of exhaust energy. This helps prevent over-boosting when the air is more dense. Now, with that said, even though the boost target and WGDC are lower, the Subarus still drive as expected. My wife's '09 WRX pulls just as hard in 1st and 2nd whether it is summer or winter. The CX-5, not so much.

Mazda should really sort this out or release a technical service bulletin about it. I don't know if it is due to DPT and/or DI, but given the drastic difference in power and the fact that there is no official notice or warning anywhere about this could get Mazda into some hot water if someone were to press the issue. We're not talking a 10-15hp drop - I swear when this issue occurs, the car isn't making much more than 160-170hp, until 3rd kicks in and then it's mostly back to normal.

Thankfully, it's my wife's car and mainly meant to be a fun commuter and travel vehicle. I still love almost everything about it, the fit & finish, the driving feel, and the acceleration ... when it isn't being limited.

I'm glad this thread exists though, as I truly thought I was going nuts or that there was something wrong with the vehicle. :)

Edit:

The really odd thing about this issue is how abrupt the changeover point is. It certainly doesn't feel like the ECU progressively pulls boost (and timing) as the temps lower. The boost-cut seems to occur at a very well-defined air temperature - almost like an all or nothing situation. Now maybe the tables for target boost and IAT compensation don't have a lot of resolution, so the steps between air temp ranges are relatively abrupt...who knows. But it sucks whatever the reason. :)

Sounds like you know your stuff. Maybe Mazda needs to learn a thing or two about this from Subaru. That said, as far as I'm aware, Subaru turbos are pretty straightforward (as far as turbos go), right? As other users have mentioned previously, maybe Mazda's dynamic pressure turbo configuration throws a wrench into the mix.

I do agree that Mazda should, at the very least, release a TSB about this so dealers are aware. I would encourage anyone experiencing this issue to contact Mazda Corporate and voice your concern, then file a complaint with the NHTSA if you deem it to be a safety issue. If the NHTSA gets enough complaints, they may begin an investigation, which would force Mazda to address the issue more publicly.
 
I do agree that Mazda should, at the very least, release a TSB about this so dealers are aware. I would encourage anyone experiencing this issue to contact Mazda Corporate and voice your concern, then file a complaint with the NHTSA if you deem it to be a safety issue. If the NHTSA gets enough complaints, they may begin an investigation, which would force Mazda to address the issue more publicly.
Agreed!
 
Wow, I'm really glad I found this thread! I've recently noticed this issue when temps fall below around -5c here in Ontario, Canada. At first I thought it might be a traction control issue but quickly ruled that out. After a bit more testing I started noticing that power returned after 3rd gear; the issue seemed mostly limited to 1st and 2nd. The acceleration difference is drastically different and has caught me out a few times when needing to quickly pull out into busy traffic. In my opinion, this is actually a little bit dangerous, as the difference in acceleration isn't minor. You become used to how a car drives and when it unexpectedly doesn't perform or behave how it should, it can be a little frustrating. Canada is cold in the winter. I typically run 94oct, so I expect at or near 250hp, even in the cold.

I have owned two Subaru WRX STis, both tuned by me, and currently driving my wife's old '09 WRX (waiting for the next STI). None of those cars exhibited this issue in the winter, stock or modded. I understand the argument that the ECU tune on the CX-5 turbo is likely attempting to prevent over-boost or protect the engine in some way. The turbo Subarus have a similar feature in the ECU maps called Wastegate Duty Cycle Intake Air Temperature Compensation (or something like iirc). So as the air temp drops, the duty cycle is lowered, allowing more bleed off of exhaust energy. This helps prevent over-boosting when the air is more dense. Now, with that said, even though the boost target and WGDC are lower, the Subarus still drive as expected. My wife's '09 WRX pulls just as hard in 1st and 2nd whether it is summer or winter. The CX-5, not so much.

Mazda should really sort this out or release a technical service bulletin about it. I don't know if it is due to DPT and/or DI, but given the drastic difference in power and the fact that there is no official notice or warning anywhere about this could get Mazda into some hot water if someone were to press the issue. We're not talking a 10-15hp drop - I swear when this issue occurs, the car isn't making much more than 160-170hp, until 3rd kicks in and then it's mostly back to normal.

Thankfully, it's my wife's car and mainly meant to be a fun commuter and travel vehicle. I still love almost everything about it, the fit & finish, the driving feel, and the acceleration ... when it isn't being limited.

I'm glad this thread exists though, as I truly thought I was going nuts or that there was something wrong with the vehicle. :)

Edit:

The really odd thing about this issue is how abrupt the changeover point is. It certainly doesn't feel like the ECU progressively pulls boost (and timing) as the temps lower. The boost-cut seems to occur at a very well-defined air temperature - almost like an all or nothing situation. Now maybe the tables for target boost and IAT compensation don't have a lot of resolution, so the steps between air temp ranges are relatively abrupt...who knows. But it sucks whatever the reason. :)
Your experiences mirrors mine. I estimate power output at 150bhp below 20*F, in 1st and 2nd gear.
 
Nice, but this doesn't seem to relate to the topic at hand unless it experiences the same boost cut that the CX-5 turbo does.
Correct; I just thought I'd throw it out there as a "side note" that included boost. :)
 
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