2021 CX-5 hesitation/back and forth feeling

Hi, just wanted to give an update. Brought in car today and the dealer said there wasn't anything wrong with the drive although imo, there clearly is. I gave them the TSB regarding "surging at low gears." Said they couldn't apply the PCM update since my VIN number and year model does not allow it. Mentioned that if they were to update it, it might mess with the current system and being that it's a 2021, it's already on the newest update. He said to basically wait it out to see if any new TSB comes out for 2021's, and that there really isn't anything he could do. I mean I am getting a little used to it but still bothers me some. I guess I'll just have to wait and see since that TSB came out in December 2020 for 2020 models which is later in the year.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
Hi, just wanted to give an update. Brought in car today and the dealer said there wasn't anything wrong with the drive although imo, there clearly is. I gave them the TSB regarding "surging at low gears." Said they couldn't apply the PCM update since my VIN number and year model does not allow it. Mentioned that if they were to update it, it might mess with the current system and being that it's a 2021, it's already on the newest update. He said to basically wait it out to see if any new TSB comes out for 2021's, and that there really isn't anything he could do. I mean I am getting a little used to it but still bothers me some. I guess I'll just have to wait and see since that TSB came out in December 2020 for 2020 models which is later in the year.
Then you want to contact Customer Experience Center, Mazda North American Operations and complain. Only this MNAO can have more samples about the problem and work on the resolution faster.
 
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2020 CX-5 Premium
Mazda seriously needs to go beyond the 6-speed auto and add more gears. Maybe 8 gears? We've had a '17 CX-5 and '20 CX-30 and the 6-speed is the one thing that annoys me about them. It just feels like it is holding the car back from greatness. More gears could make the cars faster.
 
My 2020 Signature had symptoms just like OP's. I like his analogy to a manual tranny's clutch being dropped.

The behavior has been consistent but intermittent in the 9 months I've owned the car. I mentioned it at my 5000 mile dealer oil change service and the report came back no-fault-found/normal. The advisor said it was probably turbo lag, but no, it's like the opposite: the engine would rev and then oomph, something grabs, revs drop, and away we go. Just like inexpert clutchwork.

Thing is, I'd previously owned a 2019 Signature, basically identical, and it didn't do anything like this. This would happen only intermittently, but often enough that it reduced my enjoyment of the car.

The good news: at my 10k mile service yesterday, I complained about the behavior again. This time the tech found a TSB regarding "surging" and decided that updating the drivetrain control firmware was worth a try with no possible harm.

And: it's been just a short while, but so far so good! The grabbing behavior has yet to recur in two days' driving.

I have an unusually good dealer (Capitol Mazda in San Jose) but perhaps enough examples like this will amass that Mazda corporate will roll out the update for more drivability issues.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
My 2020 Signature had symptoms just like OP's. I like his analogy to a manual tranny's clutch being dropped.

The behavior has been consistent but intermittent in the 9 months I've owned the car. I mentioned it at my 5000 mile dealer oil change service and the report came back no-fault-found/normal. The advisor said it was probably turbo lag, but no, it's like the opposite: the engine would rev and then oomph, something grabs, revs drop, and away we go. Just like inexpert clutchwork.

Thing is, I'd previously owned a 2019 Signature, basically identical, and it didn't do anything like this. This would happen only intermittently, but often enough that it reduced my enjoyment of the car.

The good news: at my 10k mile service yesterday, I complained about the behavior again. This time the tech found a TSB regarding "surging" and decided that updating the drivetrain control firmware was worth a try with no possible harm.

And: it's been just a short while, but so far so good! The grabbing behavior has yet to recur in two days' driving.

I have an unusually good dealer (Capitol Mazda in San Jose) but perhaps enough examples like this will amass that Mazda corporate will roll out the update for more drivability issues.
You want to keep watching the transmission behavior as the problem may come back like edmole1 has experienced.

Hi, folks. Thank you all for your input. I recently purchased a '19 GT with FWD and automatic. I'm experiencing the same thing -- feels just like a manual tranny car bucking in first gear at low speeds. I'll check my VIN to see if my car falls within the service bulletin fix. Unfortunately, I have 37K on the clock, so I'm just out of full factory warranty. We'll see how this goes ...

Hi, folks. Indeed, the issue was a PCM software update, which completely fixed the problem. Unfortunately, my dealership would not give me a break on the cost--$195 all in -- because my car is out of warranty, with 37K miles. He said the PCM is not covered under the powertrain warranty, which covers only internal engine/transmission parts. I'm happy the issue is resolved but it sure seems that Mazda should have picked up the cost on this one. This is my first visit to the dealership, as I just bought the car used.

The jerkiness has returned, unfortunately! It's quite annoying in normal stop and go traffic. Any suggestions on what to do next? Ask for another ECU reflash?
 
Thanks, @yrwei52. From what @edmole1 describes, if I did not know the Mazda's transmission, I'd assume he's describing DCT-tranny behavior as the internal clutches wear. Though Mazda's tranny is not a DCT unit, there might be a very similar root cause. There are several sets of clutches internal to any auto transmission that change the gears, and then there's the lock-up clutch pack, which is the one I'm casting a suspicious eye at.

I would expect that after injection of new PCM (powertrain control module) firmware, the vehicle calibrates itself to accommodate stack-up clearances in the mechanics etc. This would explain why new firmware cleared up edmole1's issues and mine. In other words, it might not be the firmware but the update process that benefited the car. Until next time.

It would be good to know how to trigger that reset/recalibration process. You know how disconnecting the battery for a while puts modern cars (including the CX-5) into learning mode? Same idea. In fact, I wonder if that same trick would recalibrate the transmission. Or maybe there's a step or two displayed on the screen of the programming computer that could be performed separately. If not, as a test, it would be interesting to flash the PCM of a misbehaving car with the same firmware rev as it currently contains.

I hope Mazda is monitoring this issue, as the fix could be really simple.

By the way, per the service documentation my 2020 Sig was flashed with firmware PX2K-188K2-B per TSB 05-002/20 ...oddly, that states "This TSB only applies to US spec vehicles with cylinder deactivation" which the turbo engines don't have. That is additional evidence it is the update process and not the firmware itself that is curing the problem ...perhaps temporarily if edmole1's experience turns out to be typical.

Does anyone know the PCM firmware update process? Is there a step that includes some sort of learning mode?

UPDATE: Per this post in a Mazda3 forum (relating to jerky acceleration), a user describes their unsuccessful attempt to reset their PCM by disconnecting the battery. Of course, who knows if they did that correctly, but on the face of it there may be another trick or procedure necessary.
 
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2005 Mazda 3 S HB 2.3L AT
I am having the same issue with my 19 CX-5 GT. I dropped my car off the service for the TSB fix. Hope they can get this fix for me, super annoying with the jerk feeling.
 
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CX5 GT
Resetting the pcm doesn’t do much. It’s not worth it to me. Resetting the tcm (i.e battery disconnect) erases the auto transmission learn curves. So it has to re-learn your driving habits for auto shifting under certain road conditions.
 
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2005 Mazda 3 S HB 2.3L AT
I got the car back and the PCM update definitely did some magic. Drove more than 30 mins combine city and freeway. Now I can feel the car run smoother than b4. At least I don't feel the jerk or hesitation.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
I got the car back and the PCM update definitely did some magic. Drove more than 30 mins combine city and freeway. Now I can feel the car run smoother than b4. At least I don't feel the jerk or hesitation.
And are you sure it’s only the PCM, not the TCM update?
 
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CX5 GT
Thats the funny thing with this tsb fix. The tsb refers to pcm update only and firmware version for each model and ecu. While we speculated earlier that its a transmission thing it comes up as engine computer firmware update. Strange.
Nothing on the tcm firmware.

And the pcm firmware version prior is the one that 'fixed' the CD recall. At least for mine when I was checking recently. My 2018 cx5 is in the affected range vins too but I havent had the fix yet.
If I decide to get it I can see if the tcm would be updated as well but highly unlikely. I havent seen many tcm updates since 2018. Mine is still on the factory version for the tcm but I got 2 pcm updates so far and I am 3+ versions after the factory ver.
 
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HardRightEdg

US 2020 CX-5 Touring AWD Soul Red
Thats the funny thing with this tsb fix. The tsb refers to pcm update only and firmware version for each model and ecu. While we speculated earlier that its a transmission thing it comes up as engine computer firmware update. Strange.
Nothing on the tcm firmware.

And the pcm firmware version prior is the one that 'fixed' the CD recall. At least for mine when I was checking recently. My 2018 cx5 is in the affected range vins too but I havent had the fix yet.
If I decide to get it I can see if the tcm would be updated as well but highly unlikely. I havent seen many tcm updates since 2018. Mine is still on the factory version for the tcm but I got 2 pcm updates so far and I am 3+ versions after the factory ver.
That wouldn't surprise me. My sense driving the thing post-TSB is they tweaked the torque curve and/or the power curve.
 
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HardRightEdg

US 2020 CX-5 Touring AWD Soul Red
And are you sure it’s only the PCM, not the TCM update?
The root problem may be in the trans design or the TCM but perhaps the TCM is not amenable to the kinds of kinds of changes needed to resolve the issues.

Post-TSB I just noticed a very slight lug in 3rd gear for the first time, not something I detected pre-TSB, some very specific combo of dropping RPMs and how gas was modulated when reaccelerating. This further leads me to believe the TSB tweaked the torque curve.
 
@onepiece715 , I have the touring spec as well in Australia so 2.5l awd. I feel the exact same thing as your description. Been looking through this forum and have been also observing the cylinder deactivation monitor,i believe it has got to do with that.
Went for a 1st inspection today, told them about it and the dealer just said its a new model doesn't have software updates,but they will check nonetheless.got a feeling they will just say its suppose to work that way...