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- '22 X3 M40i
I use 93 octane consistently. Can’t speak to the effects of <20 with lower octane.
Winter is here and my CX-5 turbo is now a 2.0L!
- Thread starter Unobtanium
- Start date
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- RDX Aspec Adv.
I use 91, E free. At my altitude it's fine. Noone runs 93, even the Lambo guys. We don't even sell it here. No difference.
Not sure if I posted in this thread, but I test drove a few 2.5T CX5's last winter (Jan-2020) when I was in the market for one. I drove 2 Signatures and 1 GTR and made sure to drive them when it was cold (0F).
All 3 exhibited this issue. 1st and 2nd gears were dogs and power came on in 3rd gear.
I was able to plug my OBDII reader and Torque app with one of them to see real time data.
There was little to no boost in first and most of 2nd gear. Maybe at the top of 2nd it started to build boost, but definitely shot up in 3rd gear.
A short stop at the grocery store and the power was back for a few blocks and then gone again. Heat soak as others have said.
Being ~40yr and still a gearhead, I'm still stuck on the power kick.
The 2.5T in the CX5 really had my attention (same as why I have a 2014 Explorer Sport).
My Explorer does not have any power loss under any conditions unless traction control kicks in (snow/ice).
I went about 180 on my new (to me) vehicle decision and ended up with a 2016 Golf R. That definitely does not have any noticeable power loss.
If the CX5 still has the turbo and resolves the cold temp power (and seat comfort for me) in another 5 years, it'll likely be a contender again.
All 3 exhibited this issue. 1st and 2nd gears were dogs and power came on in 3rd gear.
I was able to plug my OBDII reader and Torque app with one of them to see real time data.
There was little to no boost in first and most of 2nd gear. Maybe at the top of 2nd it started to build boost, but definitely shot up in 3rd gear.
A short stop at the grocery store and the power was back for a few blocks and then gone again. Heat soak as others have said.
Being ~40yr and still a gearhead, I'm still stuck on the power kick.
The 2.5T in the CX5 really had my attention (same as why I have a 2014 Explorer Sport).
My Explorer does not have any power loss under any conditions unless traction control kicks in (snow/ice).
I went about 180 on my new (to me) vehicle decision and ended up with a 2016 Golf R. That definitely does not have any noticeable power loss.
If the CX5 still has the turbo and resolves the cold temp power (and seat comfort for me) in another 5 years, it'll likely be a contender again.
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- Plano, Texas, USA
Just saw this paragraph about 2.5T turbo in owner’s manual posted by BushWickz for a different topic in another thread, it does say:
“To protect the engine from damage, the engine is designed so that it cannot be raced just after starting it in extremely cold weather.”
So it’s Mazda who designed this way ⋯
“To protect the engine from damage, the engine is designed so that it cannot be raced just after starting it in extremely cold weather.”
So it’s Mazda who designed this way ⋯
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- CX-5 Signature
Just saw this paragraph about 2.5T turbo in owner’s manual posted by BushWickz for a different topic in another thread, it does say:
“To protect the engine from damage, the engine is designed so that it cannot be raced just after starting it in extremely cold weather.”
***snipped***
So it’s Mazda who designed this way ⋯
I’d wager most turbocharged engines are designed this way so that the ECM limits boost until the oil has reached operating temperature; spinning up a cold turbo with cold oil is never a good idea. This is definitely not the issue I have experienced though. I have experienced power-loss after the engine has been running for 30min+. I still think it is related to ECM programming to limit boost based on ambient/intake air temperature and there is definitely an abrupt transition at a certain air temperature. I feel this ”protection” restricts boost too much though, especially when you’re not expecting it and need the power that you’re used to having.
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- Canada
I agree. Regarding the power-loss even after the engine has reached operating temp, it does sound like an aggressive overboost protection measure based on what others have reported about the power loss in cold temps.
7eregrine
The man, the myth, the legend
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- Land of Cleve
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- 2016.5 CX5
Maybe today. This was not the case just a few years ago. If you owned a turbo, you were either told by the dealer to let it idle after a spirited run or not gun it cold, or you already knew how to take care of it. It was always in the manual too. My 1994 Saab manual said this exact same thing. In my day... we read manuals.
Now, they make the car run slower at start up? This is why we can't have nice things.
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- CX-5 Signature
I don’t know how far back you mean but my ‘05 WRX STi had this programming too, both at start up and when at operating temp. The difference is that the air temp compensation didn’t perceptibly affect the performance after the car was up to temp.
I agree, I don’t think people understand the importance of letting the turbo cool before just shutting off the car (and i.e. oil flow). I like to read the manual too - makes for good bathroom material.
With that said, back in the day turbos weren’t as mainstream/common as they are today and were generally limited to performance vehicles. Now turbos can be found in everyday commuter vehicles and I’d wager the average consumer doesn’t care how their vehicle works - they just want it to get them from A to B. Furthermore, some automated protection makes sense given how small these turbos are and how quickly they spool at low RPMs. This helps protect the engine components from your average vehicle owner.
There are two separate issues being discussed here. The ECM restricting boost at startup, which is fairly common for turbo vehicles, and restricting boost due to air temp, regardless of whether the car is warmed up or not. The latter is the issue that I think most people are having an issue with. I wonder if this overboost protection in cold temps is an engineering issue with Mazda’s DPT or just bad calibration/oversight. Unless there is an insurmountable engineering issue with DPT in cold air temps, I don’t think the car should be pulling so much boost (and maybe timing…haven’t confirmed) in 1st & 2nd. The power loss is drastic.My 1994 Saab manual said this exact same thing. In my day... we read manuals.
Now, they make the car run slower at start up? This is why we can't have nice things.
7eregrine
The man, the myth, the legend
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- Land of Cleve
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- 2016.5 CX5
My 98 and 99 Saabs nor my 06 Saab had this tomfoolery.
No shame in admitting this. Every car manual I've owned has spent time there.I agree, I don’t think people understand the importance of letting the turbo cool before just shutting off the car (and i.e. oil flow). I like to read the manual too - makes for good bathroom material.
If it is related to temperature - and thus a signal is sent to not boost - perhaps there's a way to interrupt the signal and thus not dump the boost? I'm still in warranty, so I wouldn't do that now - but perhaps there's something in the service manual related to turbo - and you could figure out how it knows to not boost.
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- Canada
I just ordered it, but I have a CX-9. I'm not overly concerned with this issue as it doesn't seem to be as restricting on my particular car, but if there is an option to tune it out, they may have discussed it here:
JB4 for Mazda 2.5L Turbo - JB4tech.com - International Turbo Tuning Discussion
JB4 for Mazda 2.5L Turbo Mazda 2.5 Turbo
www.n54tech.com
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- '22 X3 M40i
I’ll find out in January and report back.
So you have it on your car now? How is the power compared to stock? I am considering picking one up if they have a sale at some point during the year.
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- '22 X3 M40i
I just ordered it on Sunday. Hopefully it arrives in August as they predicted. I’ll definitely do a write-up on it. I should get some sort of device for measuring performance so I can post quantitative results.
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- '22 X3 M40i
Temps dropped to 19 degrees last night and the acceleration issue in 1st and 2nd gear reappeared, even with my JB4 installed. I’ll be doing some X3 M40i shopping this weekend. I don’t think I can tolerate another winter of this.
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- RDX Aspec Adv.
I traded into a rav4 prime. Ive been loving it!
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- 2022 2.5GT
I wondered what happened to you! Hope you are well. I’m currently in a Lexus hybrid but I’ve got a 2.5 CX5 ordered and a new NX with the upgraded hybrid powertrain in and I’ll decide which to have if either of them ever turn up.
That is unfortunate. I picked up my 21 in May so we will see if Georgia temps are low enough to cause an issue. How was the JB4 in warmer weather? Did you find it worth the money?
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- '22 X3 M40i
The JB4 is great above 20 degrees. 1st gear feels about the same, but everything after that is quite noticeable. The CX-5 unit is still in its beta testing stage, so there’s slight inconsistencies in power delivery. They’re working on MAF control which will hopefully iron that out and the sub 20 degree issues.
My only complaint is in accessing the connection on the intercooler. You either have to remove the front bumper cover or contort your hand through the grill and wrestle with the connection for 20 minutes.
Is it worth it? It depends on how important a little extra scoot is to you. If you’re not in a huge hurry I’d wait until they have the MAF connection worked out.
My only complaint is in accessing the connection on the intercooler. You either have to remove the front bumper cover or contort your hand through the grill and wrestle with the connection for 20 minutes.
Is it worth it? It depends on how important a little extra scoot is to you. If you’re not in a huge hurry I’d wait until they have the MAF connection worked out.
