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

Would it be the intake air sensor or ambient air sensor that makes the ecu effect cold performance?

Not on its own. Assuming the ECU is tuned to limit performance below a specific temperature, once the sensor relays that info to the ECU, the ECU could then limit performance. But this assumes that the ECU is tuned to do that in the first place. It's something Mazda should clarify for the sake of transparency.
 
Aren't there only 2 of you with the turbo that have this issue?

More than just Unobtanium and myself have reported this. The thread created today for example by a member that took one for a test drive. Reports are outside of the forum as well but Im not going to get into that since its all documented on here somewhere.

You still have nothing proving yours is not impacted by this.
 
Aren't there only 2 of you with the turbo that have this issue?
More than just Unobtanium and myself have reported this. The thread created today for example by a member that took one for a test drive. Reports are outside of the forum as well but Im not going to get into that since its all documented on here somewhere.

You still have nothing proving yours is not impacted by this.
Actually I believe hes the only one here interested in this topic still claims theres no power loss issue below 20F on his 2.5T. Unfortunately he couldnt present any clocked data but his personal feel. He provided a LINK to Unobtanium trying to prove theres no such issue. But what I saw via the link actually proves that theres an issue as sm1ke's 0-60 run in his CX-9 with 2.5T, it clocked 8.998 sec. for 0-60 at 16F, whereas its 7.818 sec. when the temperature is warmer!
 
Actually I believe he*s the only one here interested in this topic still claims there*s no power loss issue below 20F on his 2.5T. Unfortunately he couldn*t present any clocked data but his personal feel. He provided a LINK to Unobtanium trying to prove there*s no such issue. But what I saw via the link actually proves that there*s an issue as sm1ke's 0-60 run in his CX-9 with 2.5T, it clocked 8.998 sec. for 0-60 at 16F, whereas it*s 7.818 sec. when the temperature is warmer!

Who are you? Do you own a turbo CX-5?
 
Aren't there only 2 of you with the turbo that have this issue?

Me, him, another guy on here, SavageGeese reviews, and everyone in the Facebook Mazda group...

It was also a problem with other Mazda vehicles.

https://www.mazdas247.com/forum/sho...-We-All-Know-About-Cold-Weather-Boost-Cut-But
https://www.************.com/405-ma...37-winter-woes-cold-temps-fuel-boost-cut.html
http://www.mazda-speed.com/forum2/index.php?topic=22504.0

Seems Mazda has just refined the boost cut profile is all.
 
I've seen people posting about this on the fb page too


Yeah, but most people on the FB page are the people here. They overlap.

I live in SC and the coldest it gets is 30. Compared to the 100 degree days in the summer, my 2.5T in the CX-9 feels great when it is cold (my version of cold!). Sorry suckers!

(yippy)(burnout);)
 
Interesting that there were reports of this with the speed 3s. Would really like to know if its limiting fuel, boost or both. And of course, why.

Im thinking boost based on the sound of the blowoff valve being lower when the issue is occurring. As if there is less pressure built up to blow off when getting off the gas.

Driving up hill at around 2k in 4th gear manual mode - stomp it up to about 3k then quickly let off - always activates the blow of valve. I can barely hear it when the car is in this cold weather limp mode.

I know thats not a whole lot of fact and just going by my ear, but I do have a good ear and am confident there is a difference.
 
lots of customers? I think Ive only seen one person complain about the NA 2.5 and cold weather power loss.

This is a turbo model issue/quirk.

Its not just a turbo model issue. I work in the service dept at Mazda lots of customer say the same with their non turbo 2.5s. I have drivin a lot of them off the lot turbos and non in the winter and they all do the same. It sucks to tel you the truth. Waiting to see if they come out with a update for both engines.
 
Interesting that there were reports of this with the speed 3s. Would really like to know if it*s limiting fuel, boost or both. And of course, why.

I*m thinking boost based on the sound of the blowoff valve being lower when the issue is occurring. As if there is less pressure built up to blow off when getting off the gas.

Driving up hill at around 2k in 4th gear manual mode - stomp it up to about 3k then quickly let off - always activates the blow of valve. I can barely hear it when the car is in this cold weather limp mode.

I know that*s not a whole lot of fact and just going by my ear, but I do have a good ear and am confident there is a difference.

What's your opinion of this explanation in the Mazda 3 forum?

It isn't "boost cut" it's "fuel cut" and it's because the voltage the ECU is receiving from the MAF is too high. I'm not sure about the 3s but Protege MAF max out at 5V. Anything higher than that will trigger fuel cut and if you repeatedly encounter it you will through a CEL as shane has mentioned here.

It's what you all have been saying: colder air is denser air. Greater density means more molecules per unit volume. So, for a given amount of flow, there is a larger amount of air passing by the MAF on a colder day than on a hot day. The voltage transmitted by the MAF is directly proportional the amount of air it is reading. So more air means greater voltage. Too much voltage means fuel cut. This can be alleviated through the use of a simple MAF clamp.

Anyone care to test this theory? Or is it not a plausible one?
 
Yeah, but most people on the FB page are the people here. They overlap.

I live in SC and the coldest it gets is 30. Compared to the 100 degree days in the summer, my 2.5T in the CX-9 feels great when it is cold (my version of cold!). Sorry suckers!

(yippy)(burnout);)

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.
 
He is actually pretty damn near bang-on correct. https://www.rssweather.com/climate/South Carolina/Columbia/

Yea, in Columbia, also known as the armpit! Its 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 its completely different. The average in January is below 30, at 28.

To say it doesnt get any colder than 30 in SC is just plain ignorant, its already been colder than that a handful of time already, and today is just now Winter Solstice. Lol
Granted, hes 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.
 
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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. Hell it put me outta work a few years ago because the beach got more snow than the Foothills did.

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 exactly where I was going with questioning which sensor the computer was getting info from. I think it would be possible to test.

It can easily be tested, and its most likely reading the O2 and MAF sensors, cutting fuel, and then telling the boost solenoid to cut a little boost, so all is related really. Id be curious to see this as well, but so far, Im glad I didnt buy a 2.5T. They should let everyone tune this out and keep a warranty. Lol
 
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