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

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'20 Mazda CX-5 Sig
I might be rambling here but I remember hearing Dave Coleman that they're turbo uses "scavenging exhaust" in order to spool faster and I am wondering whether this is done in purpose when its below 20 in order to prevent the damage due to cold air ?!
Negative, it’s for the purpose of spooling the turbo sooner to eliminate lag.
 
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Southwest Ohio
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'19 CX-5 diesel
I don't see many days colder than 20°F in Southwestern Ohio but we've had a few days in the teens and single digits this week. Just for fun, I tried some full throttle acceleration from a stop and the 2.2 diesel does not have this low-power issue in 1st & 2nd gear like the 2.5 turbo.
 
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'20 Mazda CX-5 Sig
That's really good data. Would you be able to post the same but showing normal boost during above 20F temps? Thank you very much for taking the time to collect this and hopefully get closer to some sort of solution for this. Or at least an explanation as to why Mazda did this.
Freezing rain all day today. I’ll give it a try next week when it warms up.
 
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'21 CX-5 CE-T
I also wonder if it's a method to avoid damage to the drive train. If you're slipping on ice and hit dry pavement at full power, it could cause major issues if the system isn't designed correctly... ie if they used the same driveline designed for the NA motor with half the power/torque.

Probably been discussed somewhere, but I wonder if other models (specifically the Mazda 3's) with the same engine experience this.
 
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'20 Mazda CX-5 Sig
Probably been discussed somewhere, but I wonder if other models (specifically the Mazda 3's) with the same engine experience this.
Sm1ke reported a slight dip in performance in his CX-9, but not nearly as pronounced as the CX-5.

I haven’t heard any complaints from the rest of the line-up, including the 3’s.
 
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Southwest Ohio
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'19 CX-5 diesel
... I also wonder if it's a method to avoid damage to the drive train...
That thought entered my head. One of the reasons I gave full throttle a try in <20°F in 1st and 2nd with my diesel ... It has very similar torque output. My output is not cut at all in 1st & 2nd gear and it has identical drivetrain to the 2.5 turbo. That (to me) rules out reasons to preserve the drivetrain components or that Mazda is worried about vehicle control.
 
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'20 Mazda CX-5 Sig
That's really good data. Would you be able to post the same but showing normal boost during above 20F temps? Thank you very much for taking the time to collect this and hopefully get closer to some sort of solution for this. Or at least an explanation as to why Mazda did this.
Here’s a comparison of two logs, one below 20 degrees Fahrenheit, and one above:

17 degrees Fahrenheit:
8B31F962-A6DF-4E44-B02E-FB20FEE7EE3D.png


32 degrees Fahrenheit:
070ACE97-570E-4195-8D1B-F06837AA6DE7.png


-Red line shows gas pedal position
-Orange line shows throttle body position
-Blue line shows actual boost
-White line is the ECU’s perceived boost (I was running Map 1, +3psi over stock)
-Green line shows RPM, which also indicates gear.
-Yellow is MPH (I ran it to about 80mph)
-Left axis=PSI
-Right axis=RPM
-Bottom=Milliseconds

So after 2 years of deliberation, it appears Mazda is using the electronic throttle body to limit power in 1st and 2nd gear when temps dip below 20 degrees. The dip in throttle shown on the 2nd graph during 1st gear was the result of me forgetting to turn off traction control, and the tires spinning briefly (don’t put any thought into that, traction control has nothing to do with the sub 20 power loss). The first log was recorded with traction control off.
 
Here’s a comparison of two logs, one below 20 degrees Fahrenheit, and one above:

17 degrees Fahrenheit:
View attachment 306451

32 degrees Fahrenheit:
View attachment 306452

-Red line shows gas pedal position
-Orange line shows throttle body position
-Blue line shows actual boost
-White line is the ECU’s perceived boost (I was running Map 1, +3psi over stock)
-Green line shows RPM, which also indicates gear.
-Yellow is MPH (I ran it to about 80mph)
-Left axis=PSI
-Right axis=RPM
-Bottom=Milliseconds

So after 2 years of deliberation, it appears Mazda is using the electronic throttle body to limit power in 1st and 2nd gear when temps dip below 20 degrees. The dip in throttle shown on the 2nd graph during 1st gear was the result of me forgetting to turn off traction control, and the tires spinning briefly (don’t put any thought into that, traction control has nothing to do with the sub 20 power loss). The first log was recorded with traction control off.
Really interesting. Thank you very much doing that it's really cool to compare the two.
 
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2014 Ford Explorer Sport, 2009 CX9(Wife's)
@jcrout7992 - Excellent post and log.
Now, I wonder if the throttle blade control can be 'hacked' to get the expected performance all the time.

Didn't mazda do something similar on the old Speed3 and Speed6 where they would start to close the throttle body above something like 5k rpm? I thought some company was able to keep it open all the way to redline (maybe I was mistaken).
 
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'20 Mazda CX-5 Sig

dynamho

Member
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02Protege 06RX8
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17M6GT 21CX5sig
Here’s a comparison of two logs, one below 20 degrees Fahrenheit, and one above:

17 degrees Fahrenheit:
[chart]
32 degrees Fahrenheit:
[chart]
Feels like a deliberate preservation limitation, but still curious about the specific reason(s).

I naively SPECULATE that it may be to avoid excessively rocking the motor through high torque, potentially cracking the cylinder head-exhaust manifold join (previous coolant leak TSB-01-013-21), whose damping or metallurgy sourcing is questionable, especially in cold temps when both metal and damping material can become brittle. I'm curious if the 2022 CX-5 will have the same limitations in the cold particularly if Mazda addressed the cyl head-exhaust manifold cracking issue properly. My guess is the 2021 model fix was a cost-economical damping solution instead of metallurgical and/or proper mounting solution.

My guess is that those who tamper with this torque in arctic temps could end up with a coolant leak problem.

I've also read about a Ford turbo getting destroyed in single digit F temps because of inadequate oil warm-up, but this can be mitigated through programming, so unlikely to be a reason.

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Anyways, also want to comment that what cash-strapped Mazda did seems clever and scrappy as usual. In the cold, the chart seems to indicate that the RPMs are held higher in each gear, essentially re-tuning it as an NA motor in the low gears to compensate for lowered boost.

I rarely have any need to launch from dig or from 2nd gear (no sensible real world scenario for that), so this is largely a non-issue for me, but still curious about the real reason.
 
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yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
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Plano, Texas, USA
Feels like a deliberate preservation limitation, but still curious about the specific reason(s).

I naively SPECULATE that it may be to avoid excessively rocking the motor through high torque, potentially cracking the cylinder head-exhaust manifold join (previous coolant leak TSB-01-013-21), whose damping or metallurgy sourcing is questionable, especially in cold temps when both metal and damping material can become brittle. I'm curious if the 2022 CX-5 will have the same limitations in the cold particularly if Mazda addressed the cyl head-exhaust manifold cracking issue properly. My guess is the 2021 model fix was a cost-economical damping solution instead of metallurgical and/or proper mounting solution.

My guess is that those who tamper with this torque in arctic temps could end up with a coolant leak problem.

I've also read about a Ford turbo getting destroyed in single digit F temps because of inadequate oil warm-up, but this can be mitigated through programming, so unlikely to be a reason.

----

Anyways, also want to comment that what cash-strapped Mazda did seems clever and scrappy as usual. In the cold, the chart seems to indicate that the RPMs are held higher in each gear, essentially re-tuning it as an NA motor in the low gears to compensate for lowered boost.

I rarely have any need to launch from dig or from 2nd gear (no sensible real world scenario for that), so this is largely a non-issue for me, but still curious about the real reason.
I don’t believe this power-reducing feature at 20°F on CX-5’s 2.5T has anything to do with preventing cylinder head cracking issue which would cause coolant leak on the 2.5T. Mazda didn’t aware the cylinder head cracking issue until very recently and issued a TSB, but this power-reducing feature when cold has been there since the 2019 CX-5 started to feature the 2.5T. And the head cracking happens on many CX-9’s too since the 2.5T has been used by it since the 2016 MY. But there’s no reports from CX-9 owners complaining the power loss issue when cold.

And BTW, the cracking only happens on the cylinder head near exhaust manifold, the exhaust manifold itself doesn’t have cracks developed on the 2.5T.
 

dynamho

Member
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02Protege 06RX8
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17M6GT 21CX5sig
Mazda didn’t aware the cylinder head cracking issue until very recently and issued a TSB, but this power-reducing feature when cold has been there since the 2019 CX-5 started to feature the 2.5T.
That's right. Good point. Hadn't considered that timeline. As it stands, my speculation is probably a wrong guess. :D

All the more curious, then.

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But what if... they saw reports of the cracks coming in with the CX9s and didn't really know what it was, so to play safe on a guessed cause, they pulled torque on the CX5 turbos, which came in 2019. When they had some confidence in the true cause of issue, they published that TSB and was glad that they pulled torque on the CX5s, lest they have more engines to fix. I'm curious now if these problems are localized to places with winters.
 
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PaulZooms

16.5 GT Sensing
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Lakewood, CO
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2016.5 CX-5 GT
The issue being discussed is only experienced in 1st and 2nd gear when flooring the accelerator.
Sorry, I just don’t get why someone would WANT or need to floor their vehicle in such cold temperatures.

I take off quite nicely from stop lights with the gas at 3/4 throttle. When I reach speed in my NA 2.5 and look back, 95% of other cars leading in adjacent lanes are 100 yards behind. The transmission has learned to shift above 5k rpm when I lean into it. The only time I do floor it is on highway on-ramps with the thought of an Italian tuneup lol. Not sure it really does much on a modern engine, but it is fun.
 
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'20 Mazda CX-5 Sig
Sorry, I just don’t get why someone would WANT or need to floor their vehicle in such cold temperatures.
This is a thread about cold weather performance issues, not whether or not someone should floor their accelerator when it’s cold out. Cold weather does not automatically equal slippery or unsafe conditions.

This is about consistent, repeatable, anticipated performance from one’s vehicle. Driver’s shouldn’t have to check the outside temperature reading before pulling out into traffic. The difference between a 6.2 and 9.2 0-60 time is a couple hundred feet. THAT is a safety issue when pulling into traffic.

Also, paying for 250hp, but only getting 150hp three months out of the year is a problem. It’s kinda like paying for a 2,500 sq ft home and randomly losing 1,000 sq ft throughout the winter. Or apply whatever analogy works for you.

I expect the things I buy to perform consistently as advertised.
 

PaulZooms

16.5 GT Sensing
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Lakewood, CO
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2016.5 CX-5 GT
This is a thread about cold weather performance issues, not whether or not someone should floor their accelerator when it’s cold out. Cold weather does not automatically equal slippery or unsafe conditions.

This is about consistent, repeatable, anticipated performance from one’s vehicle. Driver’s shouldn’t have to check the outside temperature reading before pulling out into traffic. The difference between a 6.2 and 9.2 0-60 time is a couple hundred feet. THAT is a safety issue when pulling into traffic.

Also, paying for 250hp, but only getting 150hp three months out of the year is a problem. It’s kinda like paying for a 2,500 sq ft home and randomly losing 1,000 sq ft throughout the winter. Or apply whatever analogy works for you.

I expect the things I buy to perform consistently as advertised.
Thanks for explaining. While this wouldn’t bother me, I understand why you are disappointed, perhaps p*ssed and angry.

As for checking the temperature, I always do so anyway. It’s not difficult and is important to situational awareness IMHO.