Turbo: nobody home?

I have not watched the review. I have a 2013 Speed3 and I have not experienced power loss like what was described in OP. My guess is, he was flooring it at a certain speed and it caused the transmission to downshift to a gear that put it at like 5K RPM or somewhere in the rev range where it is out of steam already. And so there was no power until the transmission would move on to the next gear.

Edit: Does turning Sport mode on, on a turbo CX-5 allow it to rev past 5k RPM? If so, then that would explain it. The car could have downshifted to a gear that put the revs at 5.5K RPM and it revved all the way to the redline before shifting gears. It would not have had full power during that time.

THIS is an interesting theory.

Any turbo owners willing to test it out?
 
I have the GTR and have experienced something like this (in non-sport mode) where it feels like the pull under hard acceleration varies a bit. The variance is barely noticeable though, not something I would describe as an issue. At no point has it ever felt slow or underpowered or laggy and I suspect its still significantly faster than the NA engine every single time.
 
THIS is an interesting theory.

Any turbo owners willing to test it out?

Never had that happen, with the diesel I had the highest it would rev in auto was 4.5K in kickdown which if I remember correctly for a 2015 car is max power. Red line was 5.2K, the auto mapping should prevent any over revving.
 
SG has talked about this before with other turbo vehicles. I think he mentioned it when reviewing the turbo Ford Taurus.

My concern with his comments on the Cx5 and this issue is that he mentions it happened when it was cold(teens). Which kind of rules out heat soak.

I suppose the cold weather thing could be a result of the many sensors in the awd system pulling power to prevent loss of traction.

With the diesel the auto will take the revs higher before changing with a cold engine, during normal driving.
 
There must be a certain set of low temperature and high humidity conditions that cause the Mazda ECU to pull timing really aggressively. Now this is only partially relevant since I have the NA engine not the turbo, but the other day I needed to accelerate around a semi on the interstate on the way to work that was only doing 55 and the engine was just completely limp. I was fresh off the on-ramp so I needed to build speed from 55 to 75 as I was moving around this semi. I kept digging into the throttle and getting nothing and finally just floored it. I've never felt the car behave in such a way before, I was literally picking up 1 mph of speed around every 2 or 3 seconds with the throttle wide open and the engine at high revs in the lowest gear it could occupy. It felt like I had at best 100 horsepower total that morning.

It was very cold and very humid with an almost frozen vapor in the air. The skyactiv engines have a lot of sensors, not just knock but also atmospheric sensors so this particular set of conditions must be bad for the engine and sends it into what almost feels like a limp mode.
 
I think it's quite relevant since it would explain what people are seeing. And if it IS timing, there will be a wide range of values. If it happens in the turbo, it would just be even more noticeable. And there would be even more reason to build such a response into the turbo.

Thanks for adding your anecdote. With enough of those we might begin to see a pattern.
 
Cold and humid conditions could mean the roads are slick. Which goes with my theory of pulling power to prevent traction loss before it even happens.
 
I think it's quite relevant since it would explain what people are seeing. And if it IS timing, there will be a wide range of values. If it happens in the turbo, it would just be even more noticeable. And there would be even more reason to build such a response into the turbo.

Thanks for adding your anecdote. With enough of those we might begin to see a pattern.

How does one build a response inside a turbo?
 
Savagegeese has mentioned in previous videos that turbos lose some of their punch with repeated short term use. It's been too long since he mentioned it to remember which review it was but he was very specific about it being a general problem with turbocharged engines. It was not directed at Mazda turbos but to all turbos.

It's not that surprising. My 2006 6s, with no turbo, will bog down a bit on hot summer days. Between the heat and having the air conditioner running there's a real loss of power. It doesn't do the same thing in the spring or fall when the air is on.
 
Long time turbo car owner (not a Mazda) here. I have experienced a situation in which there was no turbo boost when there should have been turbo boost. It was caused by an engine oil leak and the turbo had seized up. I didnt watch the video (computer problem) but there are two easy ways to know if a turbo is working: (1) a dashboard turbo boost gauge and (2) a high pitched whistle.

Did Mazda place a turbo boost gauge on the dash of 2019 CX-5 turbo models? Dont tell me Mazda didnt! I dont know because I havent driven any CX-5 Turbo models. If not, maybe theyll add it as a future enhancement. My car has one and turbo boost gauges are indispensable. He could have looked at the turbo boost gauge when he thought there was no turbo boost but there should have been and he would have known for sure. Even if the CX-5 doesnt have a built-in dash turbo boost gauge, a master vacuum gauge can be attached to the intake manifold with the hose snaking out the hood and through the drivers side window.

Theres a high pitched whistle coming from the turbo during turbo boost. He might not have heard it if the windows were all the way up (especially during the winter months) and the stereo volume turned up loud.

Intermittent problems like his are harder to track down.
 
After driving a GT-R for a few weeks now, I know exactly what Savage Geese is talking about. Sometimes I get on it and the throttle response is there but it just feels like its lacking power.

Today I noticed it on the way into work. After 8 miles at 75 I got off the highway and had to stop for a red light at the end of the exit. Light turned green and I stomped on it expecting the 310 ft pounds to thrust me to 40 in no time. Not quite what happened. It got me there just didnt push me into the seat like it should have. Shifted at about 4K into second in auto non sport mode.

I was only stopped at the light for a few seconds and its 10 degrees, so heat soaking shouldnt be the issue.
 
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After driving a GT-R for a few weeks now, I know exactly what Savage Geese is talking about. Sometimes I get on it and the throttle response is there but it just feels like it*s lacking power.

Today I noticed it on the way into work. After 8 miles at 75 I got off the highway and had to stop for a red light at the end of the exit. Light turned green and I stomped on it expecting the 310 ft pounds to thrust me to 40 in no time. Not quite what happened. It got me there just didn*t push me into the seat like it should have. Shifted at about 4K into second in auto non sport mode.

I was only stopped at the light for a few seconds and it*s 10 degrees, so heat soaking shouldn*t be the issue.

Could have very aggressive traction control response.
 
At that temperature this seems likely. AS tires are pretty hard at that point.

My Z06 F1:G2 tires gave up around 50*F, my 370Z's Pilot Super Sports hung on until around 30*F, but I have found each tire has a temperature at which it becomes absolutely worthless.

Possible reasons this is occurring:


-You are running a strong 87 that actually tests out higher, and sometimes timing is advanced, sometimes it's not.
-The butterfly valves are restricting turbo intake flow due to a design flaw/quirk.
-Traction control of some nature is cutting power.
-You're imagining things.

This is the only list of things I can come up with.
 
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Octane compensation had occurred to me also but if hes bellow 4k I dunno.

Or just a tuning quirk.
 
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